The Sensitive Gut

 | January 1, 2008

The Sensitive Gut

Dear Reader,

Out of sight, out of mind, your digestive system is working around the clock delivering the nutrients in food to your bloodstream. As long as the system is running smoothly, you tend not to think about it. Once trouble begins, however, your gut like a squeaky wheel suddenly demands your attention.

For some folks, symptoms such as diarrhea, gas, cramps, heartburn, indigestion, belching, bloating, and nausea are infrequent and tolerable, but many people experience them far more often. An estimated one in four people has frequent gastrointestinal problems that can severely disrupt a normal lifestyle. Symptoms may occur on and off for months or even years at a time, leading people to undergo unpleasant and sometimes unnecessary medical tests, spend money on questionable cures, and miss countless days of work.

Although the misery that such problems inflict is real, these ailments aren't usually the product of an illness in the conventional sense. Rather, they are functional gastrointestinal disorders. That means, unlike ulcers or stomach cancer, they can't be attributed to any physical abnormality or infection. More than 20% of people who consult a gastroenterologist learn that there's no structural abnormality to explain their complaints.

Just because we doctors can't find an "organic" cause meaning that there's no evidence of disease or a structural basis for the symptoms doesn't mean you're imagining things. The symptoms are quite real, and if they occur frequently or last more than a month, it's advisable to seek help.

You may also be relieved to know that even if your doctor can't pinpoint the cause of your symptoms, the chances are good that you can get relief. This report focuses on a number of disorders considered to be functional: reflux, functional dyspepsia, irritable bowel syndrome, constipation, diarrhea, and excessive gas.

The good news is that our ability to treat gastrointestinal disorders continues to improve. With proper knowledge and the support of the right combination of health professionals you can make changes in your lifestyle, use specific medications, find other helpful therapies that will ease your discomfort, and make the right decisions about medical treatments.

Sincerely,

Medical Editor Lawrence Friedman, M.D.

Inside the gut

The "gut." It's an ancient Anglo-Saxon word that refers to the human digestive system. Think of this marvel of nature's engineering as a perpetual food processor, constantly mixing, grinding, and transforming the meats, vegetables, fruits, and snacks that people eat into biologically useful molecules.

Nearly 30 feet long if stretched out straight, the gut is a series of hollow organs linked to form a long, twisting tube that runs from the mouth to the anus. This string of organs is known as the alimentary canal, gastrointestinal (GI) tract, or digestive tract (see Figures 1 and 2). It comprises the esophagus (or gullet), stomach, small intestine, and colon (which includes the rectum). These organs break down food and liquids carbohydrates, fats, and proteins into chemical components that the body can absorb as nutrients and use for energy or to build or repair cells. What's left is expelled by a highly efficient disposal system.

The organs of the gut are almost always moving, driven by muscles in their walls. These muscles consist of an outer longitudinal layer and an inner circular layer. The coordinated contractions of these layers push food and fluids the length of the canal, just as rolling waves deposit sand and shells on the shore. This dynamic movement along the gastrointestinal tract is known as peristalsis.

Helping with the job of digestion is the mucosa, or lining, of the mouth, stomach, and small intestine, which harbors glands that produce digestive enzymes. The salivary glands, liver, and pancreas also secrete juices that help make food soluble (dissolvable in water) so that nutrients can pass easily into the bloodstream.

Fast fact On average, the stomach holds 1 to 1.5 quarts. But records exist showing rare individuals who have an amazing 6-quart capacity.

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The digestive journey

Pop a grape, chocolate, or shrimp into your mouth. Immediately, digestion begins. In the mouth itself, the tongue and teeth help to get the process started by chewing and chopping the food so it's small enough to be swallowed. Salivary glands secrete saliva, releasing an enzyme that changes some starches into simple sugars and softens the food for swallowing. The saliva also allows the taste buds of the tongue to sense the flavors of your foods.

Swallowing is a complicated, coordinated act that begins when your tongue pushes food back into your throat or pharynx. This voluntary action sets off an involuntary chain of events that transports the food from the throat into the esophagus and down into the stomach, a journey that typically takes eight seconds.

Figure 1: Incredible journey The food you eat travels a winding 30-foot pathway known as the gastrointestinal tract or the alimentary canal. Along the way the mucosa, or surface layer of cells lining the gastrointestinal tract, produces digestive enzymes and juices that help break down food to be absorbed into the bloodstream.

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The aging GI tract

Aging takes a toll on the GI tract. Aging muscles, including the digestive muscles, contract more slowly, take plenty of time relaxing, and move their contents along at a more leisurely pace. For the most part, that's fine unless you become impatient, take drastic measures to hurry things along, or develop a condition that needs a doctor's attention. Many of the aging GI system's failures can be prevented or corrected.

The mouth. ? The changes begin at the top, in the mouth, where the number of taste buds begins to decline with age. So does the sensitivity of those that remain. The chewing muscles also begin to weaken. As a result, some older folks lose interest in food, begin to lose weight, and develop nutritional deficiencies. Losing teeth may also reduce interest in eating. Good dental care is important so that eating doesn't become a problem.

The esophagus. ? Swallowing can also become more difficult as people age. Such problems are usually the result of neurological or muscular disorders. Very old people may experience a weakening of the muscles of the esophagus, which contract less vigorously around food after swallowing. Acid reflux is often a problem in the elderly, the result of the decline in esophageal contractions and in the function of the lower esophageal sphincter muscle. However, since the esophagus may be less sensitive to acid with age, acid reflux may not result in heartburn. Instead, patients may complain of nausea or vague chest discomfort. Any new onset of difficulty in swallowing should be evaluated by a doctor because the problem could be related to cancer of the esophagus or to a motor disorder (achalasia), more common in those who are older.

The stomach and duodenum. Helicobacter pylori ₁₂ ? As people age, the stomach continues to make acid, but in many older people, acid production declines because of years of carrying infection in the stomach, leading to long-term gastritis and to atrophy of the stomach lining. While a reduction in gastric acid does not usually interfere with digestion, it can lead to two disorders that are common in the elderly vitamin B deficiency, which can result in anemia and nerve damage, and excessive bacterial growth in the small intestine, resulting in malabsorption and poor digestion. Both problems can be treated.

The colon. ? Moving one's bowels may be the most frequent gastrointestinal challenge associated with aging. The problem is usually the result of a poorly functioning or diseased large intestine. Problems with this organ can also result in diarrhea and hemorrhoids. In addition, the risk for colon cancer and polyps increases with age. In fact, one in three senior citizens has one or more polyps in the colon. That's why a screening exam called a colonoscopy is recommended on a regular basis after age 50. Since colon cancer evolves from polyps, removal of polyps will keep colon cancer from getting started. In general, people pass less stool after they reach age 65. In part, this may be the result of a change in diet to softer foods, a decreased appetite, or diminished muscular activity of the colon. Constipation may also be the result of a neurological problem (see "Constipation").

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Special section: The Stress Connection

Have you ever had a "gut-wrenching" experience? Do certain situations make you "feel nauseous"? Have you ever felt "butterflies" in your stomach? We use these expressions to describe emotional reactions because the gastrointestinal tract is sensitive to emotion. Anger, anxiety, sadness, elation: all of these emotions and many others can trigger symptoms in the gut.

The brain has a direct effect on the stomach: even the thought of eating can release the stomach's juices before food gets there. This connection goes both ways. A troubled intestine can send signals to the brain, just as a troubled brain can send signals to the gut. Therefore, a patient's distressed gut can be as much the cause as the product of anxiety, stress, or depression. That's because the brain and the gastrointestinal (GI) system are intimately connected. So intimately, says Dr. Douglas Drossman, co-director of the University of North Carolina's Center for Functional Gastrointestinal and Motility Disorders, that they should be viewed as one system, rather than two.

This is especially true in cases when the gut is acting up and there's no obvious physical or infectious cause. For such functional GI disorders, trying to heal a distressed gut without considering the impact of stress and emotion is like trying to improve an employee's poor job performance without considering his manager and work environment.

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The second brain

To appreciate the impact of stress on the gut, it is helpful to understand the similarities and connections between the brain and the digestive system. The gut is controlled by the enteric nervous system (ENS), a complex system of about 100 million nerves that oversees every aspect of digestion. The ENS is heavily influenced by the central nervous system (CNS) with which it communicates through pathways of nerves. The "second brain," as the ENS is sometimes called, arises from the same tissues as the CNS during fetal development. It has many structural and chemical counterparts in the cranial brain, including sensory and motor neurons as well as glial cells, which support and protect the neurons. And the ENS uses many of the same neurotransmitters, or chemical messengers, as the CNS.

The ENS is embedded in the gut wall and participates in a rich dialogue with the brain during the entire journey of food through the 30-foot-long digestive tract. The ENS cells in the lining of the gut communicate with the brain by way of the autonomic nervous system, which controls the body's vital functions. As part of that system, sympathetic nerves connect the gut to the spinal cord and then to the base of the brain. In addition, parasympathetic nerves pass to and from the base of the brain via the vagus nerve from the upper gut or the sacral nerves from the colon. The gut and brain use their shared neurotransmitters, including acetylcholine and serotonin, to transmit information back and forth by way of the sympathetic and parasympathetic nerves.

This two-way communication system between the gut and the brain (see Figure 4) explains why you stop eating when you're full (sensory neurons in your gut let your brain know that your stomach is distended), or conversely, why anxiety over this morning's exam has ruined your appetite for breakfast (the stress activated your "fight or flight" sympathetic nervous system, inhibiting gastrointestinal secretion and reducing blood flow to the gut).

Figure 4: Closing the pain gate Have you ever noticed that you feel pain less when you're doing something that requires all your attention? That's because pain is not a one-way street. Your brain can inhibit the pain signals from the gut. Experts explain this with the "gate control" theory. For example, receptors in your intestines, known as afferent receptors, pick up a pain signal and send it to the brain. But certain centers in the spinal cord can regulate the pain. Fibers in these "pain gates" may allow the signal to proceed to the brain, or they may "close the gate" when they receive an inhibiting signal from the brain. This process is sometimes called "down-regulation" of the pain signal. Your brain does this naturally when you are doing something that requires deep concentration, such as playing a sport intensely. Antidepressant medications can also help close the gate by blocking or inhibiting the pain signal to the brain.

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Stress and the functional GI disorders

Given how closely the gut and brain interact, it becomes easier to understand why you might feel nauseated before giving a presentation, or why you have intestinal pain during times of stress. Emotional and psychosocial factors play a role in functional gastrointestinal disorders.

That doesn't mean, however, that functional gastrointestinal illnesses are imagined or "all in your head." Psychology combines with physical factors to cause pain and other bowel symptoms. Psychosocial factors, says Dr. Drossman, influence the actual physiology of the gut, as well as the modulation of symptoms. In other words, stress (or depression or other psychological factors) can affect movement and contractions of the GI tract, cause inflammation, or make you more susceptible to infection.

In addition, research suggests that some people with functional GI disorders perceive pain more acutely than other people do because their brains do not properly regulate pain signals from the GI tract. Stress can make the existing pain seem even worse.

These observations suggest that at least some patients with functional GI conditions might find relief with therapy to reduce stress. And sure enough, a review of 13 studies showed that patients who tried psychologically based approaches had greater improvement in their symptoms compared with patients who received conventional medical treatment.

Is stress causing your symptoms? When evaluating whether your gastrointestinal symptoms such as heartburn, abdominal cramps, or loose stools are related to stress, watch for these other common symptoms of stress and report them to your clinician as well. Physical symptoms Stiff or tense muscles, especially in the neck and shoulders Headaches Sleep problems Shakiness or tremors Recent loss of interest in sex Weight loss or gain Restlessness Behavioral symptoms Procrastination Grinding teeth Difficulty completing work assignments Changes in the amount of alcohol or food you consume Taking up smoking, or smoking more than usual Increased desire to be with or withdraw from others Rumination (frequent talking or brooding about stressful situations) Emotional symptoms Crying Overwhelming sense of tension or pressure Trouble relaxing Nervousness Quick temper Depression Poor concentration Trouble remembering things Loss of sense of humor Indecisiveness

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Treating the whole body

Stress-related symptoms in the GI tract vary greatly from one patient to the next, and treatment can vary as well. For example, one person with GERD might describe an occasional, mild burning sensation in the chest, while another complains of excruciating discomfort night after night. As the severity of symptoms varies, so should the therapies, medications, self-help strategies, or even surgeries used to relieve them.

Many patients have mild symptoms that respond quickly to changes in diet or medications. If symptoms do not improve, your clinician may ask you more questions about your medical history and perform some diagnostic tests to rule out a physical abnormality, infection, or cancer. For some people, symptoms improve as soon as a serious diagnosis has been ruled out (another example of how emotional stress affects the gut!). Your doctor may also recommend symptom-specific medications. But sometimes these treatments are not enough. As symptoms become more severe, so does the likelihood that a patient is experiencing some sort of psychological distress.

Often, patients with moderate to severe symptoms, particularly those whose symptoms arise from stressful circumstances, stand to benefit from psychological treatments such as cognitive behavioral therapy, relaxation techniques, and hypnosis. Initially, some patients may be reluctant to accept the role of psychosocial factors in their illness. These treatments do not directly reduce pain or improve symptoms (although these may be indirect benefits). Rather, the goal is to reduce anxiety, encourage healthy behaviors, and help patients cope with the pain and discomfort of their condition.

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Gastroesophageal reflux disease

You enjoyed the meal, but now you're paying for it, big time. You've got heartburn an uncomfortable burning sensation radiating up the middle of your chest. Heartburn, the most common gastrointestinal malady, can hit after you eat spicy foods, when you lie down to take a nap, or perhaps at bedtime. Many women experience this sensation during pregnancy. Sometimes the pain is so intense that you may think you are having a heart attack. Although heartburn can mimic a heart attack, it is not life-threatening.

About one-third of Americans have heartburn at least once a month, with 10% experiencing it nearly every day. One survey revealed that 65% of people with heartburn may have symptoms both during the day and at night, with 75% of the nighttime heartburn patients saying that the problem keeps them from sleeping, and 40% reporting that nighttime heartburn affects their job performance the following day. This epidemic leads people to spend nearly $2 billion a year on over-the-counter antacids alone. Clearly, it's a major problem.

Heartburn is an expression of a condition known as gastroesophageal reflux disease (GERD), often called "reflux," in which acid and pepsin rise from the stomach into the esophagus, much like water bubbling into a sink from a plugged drain.

The burning sensation is usually felt in the chest just behind the breastbone and often extends from the lower end of the rib cage to the root of the neck. It can last for hours and may be accompanied by the very unpleasant, stinging sensation of highly acidic fluid rushing into the back of the throat. There may also be a sour taste in the mouth.

But the heart of heartburn and GERD is the burning behind the sternum. A variety of foods; certain emotions such as anxiety, anger, or fear; and even particular positions, like reclining or bending forward, can aggravate it. While GERD and its symptom, heartburn can be difficult to cope with, many people manage them quite well. However, other people do spend countless hours and untold sums of money looking for a way to spell relief.

Figure 5: Reflux Gastroesophageal reflux disease is an often painful condition that occurs when the lower esophageal sphincter fails to do its job of keeping digestive juices in the stomach. When the sphincter relaxes too much, irritating stomach acids surge up into the esophagus, sometimes causing inflammation and a painful burning sensation behind the breastbone known as heartburn.

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Causes of GERD

GERD is a digestive disorder affecting the lower esophageal sphincter (LES), the muscle connecting the esophagus and stomach. The LES is a high-pressure zone that acts as a barrier to protect the esophagus against the backflow of gastric acid from the stomach.

Normally, the LES works something like a gate, opening to allow food to pass into the stomach and closing to keep food and acidic stomach juices from flowing back into the esophagus. Gastroesophageal reflux occurs when the LES relaxes when it shouldn't or becomes weak, allowing contents of the stomach to rise up into the esophagus (see Figure 5). Scientists aren't sure exactly why this happens. The LES is a complex segment of smooth muscle under the control of nerves and various hormones. As a result, dietary substances, drugs, and nervous system factors can impair its function.

Factors other than malfunction of the LES contribute to reflux. In one study, about half of reflux patients exhibited impaired motility of the stomach the inability of the stomach muscles to contract in a normal fashion. This might lead to delayed emptying of the stomach, increasing the risk that acid will reflux back into the esophagus. A failure of peristaltic contractions to clear the esophagus of acid that has refluxed, a lessening of the esophageal lining's ability to resist damage, or a shortage of saliva (which has a neutralizing effect on acid) may play a part as well.

Episodes of reflux often go unnoticed, but when reflux is excessive, the gastric acid irritates the gullet and may produce pain, experienced as heartburn. Sometimes acid regurgitates as far as the mouth and may come up forcefully as vomit or as a "wet burp." Most symptoms of GERD are transient and only occur, for example, after a big meal or when a person bends over or lies down.

Overweight people and pregnant women may suffer more heartburn episodes because increased abdominal pressure contributes to reflux. Pregnant women are also more prone to heartburn because the LES relaxes in response to the high levels of the hormone progesterone that occur with pregnancy. Generally, though, GERD is uncommon in people under age 40.

Other medical conditions can also contribute to GERD. As many as 70% of asthma patients also have reflux. It's not clear, however, whether asthma is a cause or effect (see "Asthma and reflux"). Still, asthma may improve when GERD is treated. Other illnesses that may contribute to reflux include diabetes, peptic ulcers, and some types of cancer.

Functional GERD ? can occur without specific anatomical malfunction in which case it is called functional. For example, some evidence suggests that people with functional heartburn have lower pain thresholds than their healthy counterparts.

Foods that cause reflux. ? Diet can contribute to LES dysfunction. For example, alcohol can loosen the LES (and irritate the esophageal lining), as can coffee and other caffeine-containing products. Coffee, tea, cocoa, and cola drinks are all powerful stimulants of gastric acid production. Mints and chocolate, often served to cap off a meal to aid in digestion, can actually make things worse. Both relax the LES and can induce heartburn, as can fried and fatty foods. Some people say that onions and garlic give them heartburn. Others have trouble with citrus fruits or tomato products, which are irritating to the esophageal lining. High-fat foods may also trigger symptoms. If you notice that a particular food leads to episodes of heartburn, by all means, stay away from it.

Eating patterns. ? How you eat can also be as important as what you eat. Skipping breakfast or lunch and then consuming a huge meal at day's end can increase gastric pressure and the possibility of reflux. Lying down right after eating will only make the problem worse. It is best to wait three hours after eating before going to bed. And stay away from late-night snacks, too.

Smoking. ? Smoking can irritate the entire GI tract. In addition, frequent sucking on a cigarette can cause you to swallow air, increasing stomach pressure and encouraging reflux. Smoking sometimes also relaxes the LES.

Overweight and obesity. The New England Journal of Medicine ? Research has linked GERD to being overweight or obese. A 2006 study in found that weight gain increases the risk of frequent GERD symptoms even if the person's body mass index (a ratio of weight to height) remains in the normal range. The additional weight may increase pressure on the stomach, pushing its contents up. Hormones may also play a role. Even a modest weight gain may induce heartburn, so avoiding weight gain is a good idea for many reasons.

Medications that cause heartburn. improve ? Some prescription drugs can exacerbate heartburn (see Table 1). Oral contraceptives or postmenopausal hormone preparations containing progesterone are known culprits. Aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen (Advil, Motrin) and naproxen (Aleve, Naprosyn) may also pose problems. A prescription NSAID known as a COX-2 inhibitor, celecoxib (Celebrex), is widely used to relieve pain because it is designed to be easier on the stomach than standard NSAIDs. Celebrex carries a warning, however, because it has been linked to an increased risk for heart attacks and strokes, and it may still cause GI symptoms in some people. Corticosteroids, used to treat a variety of medical conditions, are also known to cause heartburn. Other drugs such as alendronate (Fosamax), used to prevent and treat osteoporosis can irritate the esophagus. And some antidepressants, tranquilizers, and calcium-channel blockers can contribute to reflux by relaxing the LES. The asthma medication theophylline may initiate or aggravate reflux in some people, thereby causing chest pain. In an interesting twist, however, studies have found that theophylline can chest pain that is not caused by reflux or heart disease.

The hiatal hernia connection. ? Hiatal hernia is a common condition in which there is an opening, or hiatus, in the diaphragm, the muscle that separates the chest from the abdomen and helps with breathing. This hiatus permits part of the stomach to protrude into the chest (see Figure 6). The resulting protrusion changes the angle at which the esophagus joins the stomach, weakening the ligaments that hold these organs in proper alignment and impairing the LES's ability to prevent reflux. Studies indicate that a hiatal hernia, particularly if large, promotes retention of acid above the hiatus and reflux of acid into the esophagus, causing irritation and pain.

Figure 6: Hiatal hernia One possible cause of heartburn is a common condition called hiatal hernia in which a portion of the stomach protrudes through the opening in a weak diaphragm, the band of muscle that separates the chest from the abdomen.

While people with small hiatal hernias (less than 3 centimeters, or about 1.2 inches) often have no symptoms, others report significant heartburn discomfort. Almost all people with large hiatal hernias have reflux. And hiatal hernias are almost always present in people with GERD who have moderate or severe esophagitis (inflammation of the esophagus). While the hiatal hernias and reflux occur independently, there is strong evidence that the two are related.

Eosinophilic esophagitis. ? Eosinophilic esophagitis is a disease characterized by the presence of eosinophils, a type of white blood cell, in the wall of the esophagus. Eosinophils, which are associated with allergic reactions, stimulate inflammation. One symptom of the condition is heartburn, although episodes of dysphagia, the feeling of food or pills sticking in the esophagus, is more characteristic. The disease often occurs in children and young adults, many of whom also have allergies or asthma. Eosinophilic esophagitis often responds to a course of the steroid fluticasone (Flovent), although in some cases symptoms may also improve with a proton pump inhibitor (PPI) such as omeprazole (Prilosec) or lansoprazole (Prevacid).

Table 1: Medications that may cause or worsen reflux
DRUG CLASS	BRAND NAME(S)		USE
Bronchodilators*
theophylline	Aerolate, Uniphyl, and others		Relieves wheezing
Calcium-channel blockers*
amlodipine	Norvasc		Lower blood pressure and improve coronary artery blood flow
diltiazem	Cardizem
nifedipine	Adalat, Procardia
verapamil	Calan, Isoptin
Nonsteroidal anti-inflammatory drugs (NSAIDs)*
aspirin	Bufferin, Ecotrin, and others		Relieve pain and inflammation
ibuprofen	Advil, Motrin
naproxen	Aleve, Anaprox, Naprosyn
Osteoporosis drugs*
alendronate	Fosamax		Build bone density
ibandronate	Boniva
risedronate	Actonel
Progestins*
medroxyprogesterone acetate		Provera, Depo-Provera	Relieve symptoms of menopause; used in oral contraceptives
norethindrone acetate		Aygestin, Micronor
Tricyclic antidepressants*
amitriptyline	Elavil, Endep		Relieve depression; occasionally used for long-term pain
nortriptyline	Pamelor, Aventyl
protriptyline	Vivactil
*Not all available drugs are listed.

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Diagnosing reflux

Many people can manage heartburn without seeking medical care, through dietary changes, over-the-counter medications (see "Self-help for reflux"), and relaxation therapy. A doctor may be helpful if your symptoms don't respond to self-help techniques and if they interfere with sleep or daily life. If you do seek your physician's advice, providing a detailed account of your symptoms will help him or her make the diagnosis.

The doctor will review your medical history and ask detailed questions about the nature of the pain and its pattern of onset. For example, he or she may ask whether symptoms are worse after you eat a heavy meal or known dietary troublemakers such as high-fat foods or dairy products. Your doctor will want to know if bending over to tie your shoelaces or lying down aggravates the symptoms and whether the pain seems linked to anxiety or stress.

_{2 2} For typical reflux symptoms, doctors usually forgo diagnostic tests and proceed straight to treatment, starting with a proton pump inhibitor such as omeprazole or lansoprazole. If this provides relief, the odds are that the diagnosis of GERD was correct. Once the symptoms are under control, the patient may either continue with the PPI or switch to a less powerful medication. That might be an H-receptor antagonist (H blocker) such as cimetidine (Tagamet), ranitidine (Zantac), or famotidine (Pepcid), or an antacid like Tums.

Asthma and reflux. Your doctor will be alert for other symptoms, such as frequent nonburning chest pain, bleeding into the gastrointestinal tract, dysphagia (difficulty in swallowing), hoarseness, or constant coughing and wheezing. Such symptoms may be associated with GERD, but could have other causes and might warrant tests to gain more information (see "Is this test necessary?").

For example, GERD is sometimes accompanied by respiratory problems such as asthmatic wheezing, coughing, or hoarseness. When asthma strikes adult nonsmokers with no history of lung disease or allergies, pH-monitoring studies sometimes suggest that GERD is the culprit. As many as 70% of patients with asthma experience reflux.

Is this test necessary? Doctors ordinarily don't put heartburn patients through costly diagnostic evaluations. However, more serious reflux symptoms, such as bleeding from the esophagus, swallowing problems, or severe symptoms that fail to respond to standard treatment for GERD, may warrant further investigation. Common tests include the following: Barium studies. The patient drinks a liquid barium mixture and then undergoes an x-ray examination of the chest and upper abdomen. The barium, a contrast medium, defines the esophagus on the x-ray image and can help the physician identify problems such as a hiatal hernia, esophageal ulcers, or a stricture (narrowing) of the esophagus. This test is called an upper GI series when the stomach and first part of the small intestine are also examined. Upper GI endoscopy. The physician inserts a flexible tube down the throat, after having first sedated the patient and depressed the gag reflex with a local anesthetic spray. The tube contains a light and camera, which allow the doctor to inspect the lining of the esophagus, assess injuries such as ulcers or strictures, and take a biopsy (a tissue sample), if necessary. Trans-nasal esophagoscopy. This diagnostic imaging technique employs a scope that is smaller than a standard endoscope. The scope is inserted through the nose (rather than the mouth) and into the esophagus. No sedation is needed, and patients can see the images and learn the results immediately. This test is not yet widely available, but may become more useful for screening patients with GERD for Barrett's esophagus (see "Complications of reflux") right in the doctor's office. pH monitoring. Used less frequently, this test monitors an individual's reflux episodes over 24 hours via a thin, acid-sensing probe inserted through the nose and positioned just above the LES. This is the best method for documenting reflux in patients who have unexplained chest pain, coughing, wheezing, or hoarseness. It's also used to assess the adequacy of acid-suppressing therapy when symptoms persist. A wireless form of the pH monitor is contained in a capsule and looks like a pill (see "Diagnosing IBS"). It is placed in the esophagus and can be used to monitor pH levels for 48 hours, during periods while the patient is both on and off acid-suppressing therapy. The wireless pH system is particularly useful in patients who do not respond to PPIs. Impedance testing. This test, approved in the United States in 2002 and becoming more readily available in clinical practice, can be done at the same time as pH monitoring. Probes equipped for this test include a pair of metallic rings that measure changes in electrical resistance that occur as food and gas pass through the esophagus.

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Complications of reflux

Although simple reflux is uncomfortable, it doesn't usually pose a danger to healthy individuals. From half to three-quarters of people with reflux disease have mild symptoms that generally clear up in response to simple measures. Over time, however, serious problems can develop when frequent relapses associated wih persistent GERD go untreated. These complications can include narrowing (stricture) of the esophagus, erosion of its lining, precancerous changes in its cells, and esophageal ulcers.

One complication, known as reflux esophagitis, is inflammation that occurs when acid and pepsin, released from the stomach, erode areas of the mucosa, the surface layer of cells that line the esophagus. Besides the burning sensation of simple heartburn, patients with esophagitis may also complain of pain behind the breastbone spreading into the back or up to the neck, jaw, or even the ears. The pain can be so intense that you may have trouble swallowing and may even think you are having a heart attack.

With esophagitis, food may feel as if it sticks in your throat before going down the gullet. Hot drinks are unpleasant to swallow, and you may have some nausea. You may also regurgitate some acid fluid into your throat, resulting in a cough. The inflammation of the esophagus can even lead to bleeding. Endoscopy is necessary to confirm the diagnosis of esophagitis and locate any associated ulcers or strictures. Bleeding ulcers in an inflamed esophagus may require aggressive treatment, such as blood transfusions and, to stop the bleeding, a probe passed through an endoscopic tube to apply electricity or heat, or to inject blood vesselconstricting agents into the bleeding site. Strictures may need to be dilated through endoscopy, using a balloon or other special dilator. About one-third of patients who need this procedure require a series of treatments to fully open the passageway.

Another complication of chronic esophageal inflammation is Barrett's esophagus, an abnormality in which taller cells resembling those that line the small intestine replace the squamous or flat cells that normally line the lower esophagus. The condition, a potential consequence of longstanding GERD, is caused by long-term and severe exposure to acid from the stomach and bile from the small intestine. Barrett's esophagus can, over time, develop into cancer, so patients are urged to have regular endoscopic evaluations (including biopsies) to identify very early malignant changes. Persons most at risk are those usually middle-aged white men who developed GERD at an early age and have had it for many years.

One study reported a higher risk for esophageal cancer in GERD patients, whether or not they have Barrett's esophagus. Fortunately, only a very small percentage of patients with GERD will develop esophageal cancer. Some experts think it's the reflux of bile, in addition to acid, that heightens the risk for esophageal cancer.

GERD can also result in dental problems, including loss of tooth enamel. And it can cause spasms of the vocal cords (larynx), blocking the flow of air to the lungs. One study has reported that such spasms may cause sleep apnea, a condition in which breathing frequently stops for brief moments during sleep.

ROME III: Diagnosing GI disorders Doctors diagnose functional gastrointestinal disorders (including functional heartburn) based on a patient's symptoms. To make diagnosis as consistent as possible, a group of more than 100 international experts created the Rome criteria. Rome III, published in 2006, provides the most current diagnostic criteria for all of the functional gastrointestinal disorders presented in this report.

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Self-help for reflux

Modifying diet and lifestyle remains the foundation for treating the symptoms of reflux. Your goal is to prevent the problem by keeping stomach contents where they belong and staying away from foods that loosen the LES.

Here are some prevention tips for people troubled by symptoms.

Eat smaller meals. ? A large meal remains in the stomach for several hours, increasing the chances for gastroesophageal reflux. Therefore, anyone who suffers from this problem should distribute his or her daily food intake over three, four, or five smaller meals.

Relax when you eat. ? Stress increases the production of stomach acid, so make meals a pleasant, relaxing experience. Sit down. Eat slowly. Chew completely. Play soothing music.

Relax between meals. ? Relaxation therapies such as deep breathing, meditation, massage, tai chi, or yoga may help prevent and relieve heartburn.

Remain upright after eating. ? You should maintain postures that reduce the risk for reflux for at least three hours after eating. For example, don't bend over or strain to lift heavy objects.

Avoid eating within three hours of going to bed. ? Do not eat bedtime snacks.

Lose weight. Excess pounds increase pressure on the stomach and can push acid into the esophagus.

Loosen up. ? Avoid tight belts, waistbands, and other clothing that puts pressure on your stomach.

Avoid foods that burn. Abstain from food or drink that increases gastric acid secretion, decreases LES pressure, or slows the emptying of the stomach. Known offenders include high-fat foods, spicy dishes, tomatoes and tomato products, citrus fruits, garlic, onions, milk, carbonated drinks, coffee (including decaf), tea, chocolate, mints, and alcohol. The list is long, but you're likely to see a substantial improvement if you cut out such foods.

Stop smoking. ? Nicotine stimulates stomach acid and impairs LES function.

Chew gum. It can increase saliva production, soothing the esophagus and washing acid back down to the stomach.

Consult your doctor about your medications. ? Drugs that can predispose you to reflux include aspirin and other NSAIDs, oral contraceptives, hormone replacement therapy, narcotics, certain antidepressants, and some asthma medications (see Table 1).

Raise your bed's head at night. ? If you're bothered by nighttime heartburn, elevate the head of your bed by placing a wedge (available in medical supply stores) under your upper body. But don't elevate your head with extra pillows. That makes reflux worse by bending you at the waist and compressing your stomach.

Exercise wisely. ? Wait at least two hours after a meal before engaging in vigorous physical activity, giving your stomach time to empty.

Do you have functional heartburn? According to the Rome III criteria for a diagnosis of functional heartburn, a patient must have experienced all of the following for the past three months, with symptoms starting at least six months before diagnosis: burning discomfort or pain behind the breastbone no evidence that symptoms are caused by acid reflux from the stomach or esophagus absence of structural disorders that interfere with the movement of food down the esophagus.

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Antireflux drug therapy

_{2 2 2 2} How do you spell relief? Nonstop advertising has acquainted most people with antacids, the least expensive treatment for heartburn. These work by reducing the acidity of refluxed material. Almost as well known are H-receptor antagonists (H blockers) and proton pump inhibitors (PPIs). The former cost a little more than antacids, but are generally more convenient, and some can be purchased over the counter. PPIs are more effective than either antacids or H blockers, but tend to be costly. In severe cases, physicians may favor combining various antireflux drugs, such as over-the-counter antacids and H blockers or PPIs and prokinetic drugs that increase gastric emptying. However, PPIs without additional medications are generally preferable to combinations.

Let's look at them in the order in which physicians typically recommend or prescribe their use.

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Herbal remedies

Some people have found herbs and other natural remedies to be helpful in the treatment of heartburn symptoms.

Chamomile. ? A cup of chamomile tea may have a soothing effect on the digestive tract. People with ragweed allergy should avoid chamomile.

Ginger. ? The root of the ginger plant is another well-known herbal digestive aid and has been a folk remedy for heartburn for centuries.

Licorice. ? This remedy has proved effective in several studies. Licorice is said to increase the mucous coating of the esophageal lining, helping it resist the irritating effects of stomach acid. Deglycyrrhizinated licorice, or DGL, is available in pill or liquid form. It is considered safe to take indefinitely.

Other herbs. ? A variety of other remedies have been used over the centuries, but scientific evidence to confirm their effectiveness is insufficient. Catnip, fennel, marshmallow root, and papaya tea have all been said to aid in digestion and act as a buffer to stop heartburn. Some people eat fresh papaya as a digestive aid. Others swear by raw potato juice, three times a day. Naturopathic followers also tout a homeopathic remedy with the unappetizing name of vomit nut as a heartburn fix. However, these herbal remedies do not undergo testing for safety and effectiveness by the federal government and are not approved by the FDA.

How to distinguish GERD discomfort from a heart attack It's important to consider the possibility that chest pain may mean a heart attack instead of heartburn. Symptoms associated with GERD can mimic the pain of a myocardial infarction (heart attack) or angina (chest pain caused by diminished blood flow through the coronary arteries), especially when the sensation is constricting rather than burning in nature. It can be dangerous to assume that your chest pain is caused by reflux. People with known reflux disease should always seek medical attention if they experience chest discomfort brought on by exercise, which may signal either angina or a heart attack. How can you be sure that you have heartburn, not a heart attack? The main thing to determine is the severity and length of your chest pain. If it's a severe, pressing, or squeezing discomfort, it may be a heart attack. And heart attack pain lasts awhile. If it goes away in five to 10 minutes, it's probably not a heart attack. It could be angina, however, which does require a visit to the doctor and treatment. It's important not to dismiss chest tightness, especially if it follows physical exercise.

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Surgical options for reflux

Medication and lifestyle changes can successfully control 95% of GERD cases, but for a few patients, surgery is the best option. For example, surgery may be preferable for young patients who find the prospect of taking PPIs for life unappealing. Other indications for surgery are occasional cases of erosive esophagitis that do not improve with drug therapy, strictures that recur despite treatment, or pneumonia or recurrent respiratory problems due to acid reflux that don't improve with drug therapy.

The goal of surgery is to tighten the LES. The operations are generally effective and may eliminate the need for all GERD medications.

Fast fact About 90% of patients are free of heartburn in the months following reflux surgery. But a follow-up study showed that within 10 to 13 years, many such patients eventually needed to start taking heartburn medications again.

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Functional dyspepsia

You're having trouble with your stomach. You feel uncomfortable. It's not heartburn, but it seems to be related to eating. You feel bloated and full or have a burning pain. You complain of nausea, or sometimes you even vomit. You think you might be having "indigestion."

dys, peptein, Doctors call it dyspepsia literally, "bad digestion." The word is derived from the Greek which means bad, and which means "to cook" or "to digest."

The term functional dyspepsia (FD) is used to describe persistent upper abdominal pain or discomfort that's often related to eating, and for which there is no identifiable cause such as peptic ulcer disease. Because peptic ulcer disease produces similar symptoms, functional dyspepsia is sometimes called nonulcer dyspepsia.

In most cases, the uncomfortable upper abdominal symptoms appear after eating, but there's no difficulty in swallowing. Sometimes the discomfort begins during the meal, sometimes about half an hour later. It tends to come and go in spurts over a period of about three months.

This condition affects about a quarter of the population twice as many as have peptic ulcer disease and it hits men and women equally. It's responsible for a significant percentage of visits to primary care doctors. Many people suspect they're suffering from ulcers, but are found not to be. The cause of FD is unknown. Even more frustrating, there's no surefire cure.

The first question on most people's minds is "Do I have an ulcer?" It's not an unreasonable question, considering that 10% of Americans develop a peptic ulcer at some time in their lives. And it's important to answer it quickly. Ulcers can have serious complications, while FD generally does not. Ulcers can be treated with medications, while in most cases medications don't do much to remedy FD.

Peptic ulcers are raw, crater-like breaks in the mucosal lining of the digestive tract. They occur in the stomach and duodenum and are linked to the erosive action of gastric acid and sometimes to a reduction in protective mucus. In essence, the stomach, which is designed to digest foods, is digesting a part of its own lining. These localized, generally circular craters are rarely more than an inch in diameter.

Helicobacter pylori, H. pylori In the early 1980s, researchers made a major discovery. They identified a spiral bacterium with an affinity for the stomach, as a major culprit in ulcer disease. is the cause of many peptic ulcers (see Figure 8). At least 90% of people with duodenal ulcers and 75% to 85% of those with gastric (stomach) ulcers are infected with this organism.

Figure 8: How an ulcer starts Helicobacter pylori The corkscrew-shaped bacterium attaches to the surface of the stomach by twisting through the mucus that protects the stomach lining from corrosive gastric juices.

H. pylori The percentage of ulcers that are not caused by has increased; researchers are not yet sure why. Other causes of ulcers include irritating substances such as aspirin, ibuprofen, and other NSAIDs. Cigarette smoking impairs the healing of ulcers, and stress appears to aggravate ulcer symptoms. Studies show there's also a genetic component, as peptic ulcers sometimes run in families. They occur more often in people with type O blood than in those with other blood types. Sometimes there is no known cause.

Is it an ulcer? Aside from dyspepsia, other symptoms that may point to an ulcer, rather than to FD, include: evidence of bleeding, such as passing black stools or vomiting blood or material that resembles coffee grounds repeatedly vomiting large amounts of sour juice and food, which can signal an obstructing ulcer sudden, overwhelming pain a rare but frightening signal that the ulcer has perforated the stomach or duodenal wall.

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Diagnosing FD

People with functional dyspepsia have the symptoms of an ulcer without the ulcer itself. Both conditions seem to be stress-related and affect people of all ages. In many cases, the symptoms of both respond to treatment with a placebo pill (which contains no active ingredient). In both conditions, pressing on the patient's abdomen may produce tenderness.

₂ Your doctor's goal will be to confirm or exclude the possibility of an ulcer. During a medical exam, your clinician will ask questions about your medical history and about the frequency of the pain, how long it's persisted, and when it's most severe. Discomfort that feels worse on an empty stomach and is relieved by eating suggests a duodenal ulcer, although the diagnosis isn't definitive. Ulcer pain often awakens a person during the night. If this pain is relieved by antacids, H blockers, or proton pump inhibitors taken at bedtime, it may indicate an ulcer. Your physician will also address other health habits, such as whether you smoke or drink alcoholic beverages, and will want to know if other family members have ever been diagnosed with an ulcer.

To confirm the presence of an ulcer, the doctor may order an endoscopy or upper GI series. However, some physicians are hesitant to order these tests because in most instances of dyspepsia, results are negative and are unlikely to influence initial treatment strategies. Still, a patient will no doubt take comfort in learning that he or she doesn't have an ulcer.

Do you have functional dyspepsia? The Rome III criteria state that functional dyspepsia must include one or more of the following for the past three months, with symptoms beginning at least six months before diagnosis: bothersome feeling of fullness after eating early feeling of fullness pain in the upper abdomen burning in the upper abdomen and: no evidence of structural disease (including at upper endoscopy) that is likely to explain the symptoms.

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Tests and medication

H. pylori As a first step toward both diagnosis and treatment, your doctor will probably prescribe one or more drugs that curtail acid secretion (see Table 2) to see if the dyspepsia clears. The doctor may also order a fecal, blood, or breath test to detect the presence of bacteria. If the test is positive, the doctor will prescribe antibiotics to eradicate the bacteria. If symptoms have not improved after a few weeks, the next step will probably be endoscopy to check for ulcers (see Figure 9).

People over age 55 (some experts say over age 45) with a new onset of dyspepsia and those with a family history of gastrointestinal cancers should be promptly evaluated for underlying cancer. Prompt evaluation is also needed for patients whose dyspepsia is accompanied by additional worrisome symptoms, such as weight loss, dysphagia (difficulty swallowing), gastrointestinal bleeding, or anemia (low blood count). Only after tests and drug trials fail to pinpoint another cause can the condition be labeled FD.

Figure 9: Upper GI endoscopy Depending on your symptoms, your doctor may want to look at your esophagus and stomach with an endoscope, a flexible tube with a light and camera at the end. With local anesthesia, you will be asked to lie on your side as the doctor gently slides the scope through your mouth and down your esophagus into the stomach, while watching for lesions on a video monitor.

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Causes of FD

Although there are several theories, no one really knows what causes FD. Many experts don't think that excess gastric acid is to blame. Studies have found no irregularities in acid secretion in dyspeptic patients and no correlation between symptoms and increased acid production. But the theory remains under consideration, as does the possibility that the abdominal pain associated with FD results from acid leaking through the gastric or duodenal mucosa, which has been altered in some way. Some other ideas include:

Visceral hypersensitivity. ? Many experts believe that patients with FD are more sensitive to pain than people without FD, and that they may have a lower threshold for pain than their healthy counterparts.

Abnormal motility or sensation. ? The symptoms of FD may reflect abnormal motility that is, a problem with the movement of the digestive tract.

Stress, anxiety, or other psychological factors. ? Although scientific data are scarce, psychological stress may be important in the development of some cases.

H. pylori infection. H. pylori H. pylori H. pylori H. pylori ? While the role of infection as a cause of ulcers and gastritis is well established, its involvement in FD is unclear. infection is only slightly more common in people with FD than in the general population. Although the organism may contribute to FD symptoms in some cases, there's currently no way to distinguish these people from those in whom does not cause FD. In most cases, eradicating with antibiotics doesn't significantly improve FD symptoms.

Duodenitis. ? Another condition that might produce symptoms of FD is duodenitis, a long-term inflammation of the lining of the duodenum. However, less than 20% of people with FD have this condition.

Diet. ? Certain fatty foods are often blamed for dyspepsia. This connection makes sense because fat ingestion not only delays gastric emptying but also increases distension of the stomach. Substances like alcohol and coffee may also aggravate symptoms.

Drugs. ? Nonsteroidal anti-inflammatory drugs (NSAIDs), especially aspirin, can cause dyspepsia, ulcers, and gastritis. Other drugs, such as opiates, iron preparations, and digitalis, may also cause dyspepsia.

Functional dyspepsia: What else could it be? At least some of the distress associated with FD is due to the nagging fear that a more serious condition may be going undetected. This is rarely the case, especially when symptoms persist for months or years without worsening. Fortunately, more serious ailments have characteristics that set them apart from FD (see Figure 10). Gallstones. Stones can dwell silently in the gallbladder or can produce painful attacks, typically after a large, high-fat meal, if the gallbladder contracts and a stone lodges in its neck. The pain is usually located just under the right rib cage and may radiate to the right shoulder or back. Stomach cancer. Malignancies of the stomach generally occur later in life, after age 50. Tumors that burrow into the stomach wall often produce symptoms that resemble those associated with ulcers. Eating a full meal can become impossible if growths extrude into the hollow of the organ or spread through the stomach wall, making it too stiff to expand. Warning signs include bleeding, persistent vomiting, a constant sense of nausea or fullness that interferes with normal eating, and weight loss. Stomach cancer usually requires the surgical removal of all or part of the stomach. Figure 10: Other causes of pain Other conditions that have symptoms similar to functional dyspepsia include gallstones, which can block the neck of the gallbladder, causing painful inflammation, or cancer of the lining of the stomach, which can create a sensation of painful bloating.

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Treating FD

No truly effective drug exists to treat FD. Many patients respond no better to drugs than to placebo. It is noteworthy, however, that in almost all clinical trials, 25% to 60% of patients respond to medications, and therefore doctors often recommend them, including over-the-counter antacids and Prilosec.

Herbal remedies may also be worth a try. In several clinical trials, a combination of enteric-coated peppermint oil and caraway oil successfully reduced fullness, bloating, and gastrointestinal spasms in patients with functional dyspepsia. Enteric-coated means that the preparation is able to pass through the stomach and won't dissolve until it reaches the small intestine.) Be aware, however, that peppermint oil may trigger reflux in people who are predisposed to it.

Doctors may recommend other medications. Anticholinergic medications that decrease contractions in the GI tract, such as hyoscyamine (Levsin), may be used for up to four to six weeks. Simethicone, which rids the gut of gas bubbles, is safe and may help if you have both dyspepsia and flatulence. Finally, the doctor may prescribe a low dose of a tricyclic antidepressant such as amitriptyline (Elavil, Endep). Some studies have founds that tricyclics improve symptoms.

Emerging treatments. The New England Journal of Medicine, Itopride, a dopamine D2 antagonist that is widely prescribed in Japan for patients with functional dyspepsia, is a prokinetic drug that stimulates gastric motility and may also affect gastric accommodation and hypersensitivity. In a 2006 study in itopride significantly improved FD symptoms.

Drug developers are also looking into medications that can help the stomach distend normally during a meal, so that more food can be ingested before a feeling of uncomfortable fullness sets in. One area of interest is a class of drugs that includes sumatriptan (Imitrex), a drug marketed for migraine headaches, and buspirone (Buspar), a drug used for anxiety.

In addition, studies looking at the effects of selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs) on functional dyspepsia are under way.

Lifestyle modifications for FD Body position, diet, exercise habits, and more can help. Make good eating choices Avoid foods that trigger symptoms. Eat small portions and avoid overeating. Eat smaller, more frequent meals. Chew your food slowly and completely. Avoid activities that result in swallowing excess air, such as smoking, eating quickly, chewing gum, and drinking carbonated beverages. Don't lie down within two hours of eating. Keep your weight under control. Reduce stress Use stress reduction techniques, including relaxation therapies, cognitive behavioral therapy, or exercise. Reduce fatigue Get enough rest. Go to bed and get up at the same times each day. Avoid caffeine after noon. Exercise Perform aerobic exercise three to five times a week for 20 to 40 minutes per session. Don't exercise immediately after eating.

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Irritable bowel syndrome

Another common intestinal disorder with a myriad of unpleasant symptoms is irritable bowel syndrome (IBS). IBS affects millions of people, but has no known cause and no effective remedy. It is the most common diagnosis made by gastroenterologists and accounts for as many as 3.5 million physician visits and 2.2 million prescriptions per year. Today, IBS affects as many as 20% of adults in North America, with women being twice as likely as men to experience it.

Irritable bowel syndrome may well be the most challenging functional GI disorder for patients and doctors alike. Several studies have found that patients with IBS have a significantly lower quality of life than patients without the syndrome and that the illness is seriously underdiagnosed. Through the years, IBS has been called by many names spastic colon, spastic bowel, colitis, mucous colitis, and functional bowel disease. None of these names is quite accurate.

A 2005 survey of 1,713 people who met the criteria for IBS found that 22% had IBS symptoms for more than 10 years, and another 41% had experienced symptoms for one to five years. Sixty-seven percent said their most recent episode occurred within the past three months. Ninety-one percent had used at least one over-the-counter medication for IBS during the past year, and 46% had used at least one prescription drug. Over all, they scored lower than the average for the U.S. population in all quality of life categories surveyed, including bodily pain, general health, vitality, social functioning, and mental health. All in all, too many people are suffering from this perplexing condition.

If you have some of the symptoms of IBS, you may need to seek medical attention if you are truly miserable or worried about the possibility of more serious illness. However, there may be good reason not to seek medical attention; the cost of such care can be high. In rare cases, IBS patients undergo unnecessary surgery. And the drugs used to treat IBS are costly, even though studies have not proved most of them to be more effective than placebos. On the other hand, studies have shown that any drug used to treat an IBS patient exhibits a strong placebo effect.

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What is IBS?

IBS usually begins in your late teens, 20s, or 30s. You're a relatively healthy person; then one day you begin to suffer intermittent cramps in the lower abdomen. You have to move your bowels more often than usual, and when you have to go, you have to get to a toilet right away. Your stools are loose and watery, possibly containing mucus. Sometimes, you feel bloated and full of gas.

After a while, the cramps return, but this time when you try to go to the bathroom, nothing happens. You're constipated. And back and forth it goes diarrhea, then constipation, and pain and bloating in between. Some people with IBS alternate between constipation and diarrhea, while others always have one without the other. Irritable bowel syndrome is the catchall term for this mixed bag of symptoms.

It's a common disorder, with no known cause. The most frequently reported symptom is pain or discomfort in the abdomen. People with IBS generally feel their pain subside after a bowel movement or passing gas. But they also may feel that they haven't fully emptied their rectum after a movement.

While some patients have daily episodes or continuous symptoms, others experience long symptom-free periods. These patterns make it hard to know whether someone has IBS or some occasional complaint that's part of the bowel's normal response to stress or diet. Whether it is IBS usually depends on its frequency. The formal criterion for diagnosis is that symptoms have occurred for at least three days per month during the preceding three months. If you have recurring abdominal pain without constipation or diarrhea, your symptoms suggest a different disorder known as functional abdominal pain syndrome. IBS, on the other hand, is accompanied by changes in bowel movement.

IBS has no organic basis that is, there's no physical abnormality or disease at the root of the problem. And doctors don't regard IBS as a forerunner of more serious diseases, such as ulcerative colitis, Crohn's disease, colon cancer, or stomach cancer (see "Irritable bowel syndrome: What else could it be?").

Irritable bowel syndrome: What else could it be? A number of gastrointestinal diseases can cause nonspecific symptoms similar to those of IBS. Diverticular disease. Small, finger-like sacs or pouches known as diverticula may protrude off the colon's inner lining, where the blood vessels enter the colon, piercing its walls and causing areas of weakness. Although the condition is most common after age 50, younger people occasionally develop diverticula. When a diverticulum becomes inflamed or infected, the condition is called diverticulitis. The symptoms of diverticulitis are much more intense than those of IBS and include severe left lower abdominal pain, chills, fever, and an elevated white blood cell count. Treatment of diverticulitis involves a liquid diet to let the bowel rest and antibiotic therapy to clear the infection. After the immediate inflammation has stabilized, patients switch to a steady high-fiber diet to help prevent flare-ups. Although patients are often advised to avoid nuts and seeds, there is no scientific support for this recommendation. Surgery may be required for complicated or recurrent diverticulitis. Inflammatory bowel disease (IBD). Inflammatory bowel disease has a wide variety of symptoms, including persistent abdominal pain, diarrhea, rectal bleeding, fever, and weight loss. Crohn's disease and ulcerative colitis, two conditions that together are referred to as inflammatory bowel disease, often have similar symptoms and are treated in similar ways, yet physicians regard them as distinct. Crohn's disease can occur anywhere in the gastrointestinal tract, from the mouth to the anus, but it's usually found at the end of the small intestine (ileum), in the colon, or both. It involves the full thickness of the bowel wall and may burrow into nearby organs. The bowel wall becomes thickened as well as constantly inflamed, and leakage of intestinal contents from the bowel can cause internal abscesses. A leak (fistula) that allows intestinal material to pass into the abdomen may require surgery. Severe bleeding is not likely. Crohn's disease usually appears in young people, who develop pain in the right side of the abdomen, a low-grade fever, and perhaps changes in bowel movements. Some patients develop an abscess or fistula around the anus. In some cases, surgery is needed to treat a complication of the disease, such as bowel obstruction. About 40% to 60% of those with Crohn's eventually need surgery to remove damaged areas of their small intestine or colon. Ulcerative colitis is characterized by inflammation of the lining, or mucosa, of the colon. Like IBS, it can cause lower abdominal pain and diarrhea. Unlike IBS, the stool generally contains blood, and bowel symptoms may be accompanied by fever, weight loss, an elevated white blood cell count, and a variety of skin lesions and arthritis. Ulcerative colitis is easier to diagnose than Crohn's disease and is treated with many of the same medications. While drugs cannot cure IBD, they are effective in reducing inflammation. The drugs used most commonly are aminosalicylates (cousins of aspirin); steroids (potent anti-inflammatory agents) such as prednisone and budesonide (Entocort); immunosuppressants like azathioprine (Imuran) and 6-mercaptopurine (Purinethol); and antibiotics. Biologic agents, including infliximab (Remicade) and adalimumab (Humira), have also proved effective for selected patients with IBD. Natalizumab (Tysabri), an immunomodulator, was approved, with restrictions, to treat Crohn's disease. Colorectal cancer. Colorectal cancer is the third most common form of cancer in both men and women, with an estimated 154,000 new cases diagnosed in the United States each year. Early on, colon cancer causes no symptoms. Later, its symptoms can be similar to those of IBS abdominal pain, cramping, bloating, gas pains, and a change in bowel patterns. In addition, blood in the stool or rectal bleeding is often present. Advanced cancer is likely to cause bloody bowel movements, severe constipation if the intestine is obstructed, and weight loss. Thus, it's vital to get checked without delay should these symptoms occur. The good news is that colon cancer can be prevented in most cases through screening. Almost all precancerous growths (polyps) can be spotted and removed during a colonoscopy. Early-stage, localized colon cancers are curable by surgery in 90% of cases. Celiac disease. Also known as celiac sprue, celiac disease is a genetically based disorder that damages the small intestine and may result in debilitating symptoms. As many as one million Americans may have the disease, which clusters in families, primarily occurring in whites of European ancestry. It often goes undiagnosed. When people with celiac disease eat foods containing gluten a protein found in wheat, rye, and barley their immune systems attack and destroy the tiny finger-like projections lining the small intestine. A simple blood test for higher-than-normal levels of antibodies is the first step in diagnosing the disease. If the test is positive, a biopsy of the small intestine, performed through a standard endoscope, can confirm the diagnosis. Treatment is straightforward: a gluten-free diet. Symptoms often improve within days, and the small intestine gradually returns to normal function.

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Causes of IBS

IBS is probably not a single disease, but rather a set of symptoms that stem from a variety of causes. It may be generally described as a disorder in the functioning of the gastrointestinal tract. Some experts suspect that IBS involves disturbances in the nerves or muscles in the gut. Others believe that abnormal processing of gut sensations in the brain may hold the key, at least in some cases.

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Diagnosing IBS

Because there are no specific tests for IBS, the illness must be diagnosed based on symptoms and by the process of elimination, often with the use of tests for other conditions. Fortunately, a diagnosis usually can be made with a single visit to a doctor.

The doctor takes a complete medical history, including a careful description of your symptoms. A physical exam and some routine laboratory tests are likely to be part of the exam, and a stool sample is useful for evidence of bleeding. In some cases, the doctor may also recommend diagnostic procedures that involve viewing the inside of the colon with a scope inserted through the anus, such as sigmoidoscopy or colonoscopy. The doctor may also order an x-ray. But the goal is to use as few costly, invasive tests as possible. To accomplish this, experts in the treatment of gastrointestinal illnesses have developed a set of criteria to help identify people with IBS (see "Do you have IBS?").

The doctor will also ask whether your symptoms started after an episode of gastroenteritis, or if they seem to be triggered by specific foods or medications, particularly milk products (to rule out lactose intolerance) and foods and beverages that contain fructose or sorbitol. You may need to keep a food diary for a few weeks to help identify foods that provoke symptoms.

It's especially important to consider emotional and psychological triggers. The doctor will want to know what prompted the visit and will ask about your lifestyle and stress level. It's not unusual for a traumatic life event such as divorce or the loss of a job to wreak havoc on the bowels and the psyche.

Other symptoms that accompany the pain may offer clues. If there is pain in the lower abdomen and a change in bowel movements, an abnormality in the large intestine may be present. A combination of abdominal pain and fever can signal inflammation (for example, diverticulitis), which requires immediate medical attention.

Another major diagnostic clue is bleeding from the digestive tract. People with IBS can have rectal bleeding, but IBS does not cause bleeding. Instead, bleeding reflects another cause, such as hemorrhoids. Bright red blood comes from the lower digestive tract, while black, tarry blood comes from the upper GI tract. If there is bleeding, more tests must be performed to determine the cause.

During the physical exam, the physician will look for tenderness in the abdomen. If the tenderness is located in the lower right part, it may signal ileitis or appendicitis, and in the upper right part, gallstones and inflammation of the gallbladder. The doctor will also check for a mass, which might be a tumor, a large cyst, or impacted stool. If the patient has IBS, the physical exam will usually not reveal anything other than perhaps a mildly tender abdomen. And lab tests are generally normal in IBS patients. A digital rectal exam is also usually part of the evaluation to check for masses in the rectum and, in men, the prostate. If a serious disorder is suspected, more tests will be ordered immediately.

Do you have IBS? According to the Rome III criteria, you have IBS if you have had recurrent abdominal pain or discomfort at least three days a month in the past three months, beginning at least six months ago, and two or more of the following: improvement in symptoms after a bowel movement a change in the frequency of stool accompanying the onset of pain or discomfort a change in the form (appearance) of stool accompanying the onset of pain or discomfort. The following additional symptoms are not essential for diagnosis, but they support the diagnosis and may also be used to identify certain types of IBS: abnormal stool frequency (more than three bowel movements per day or less than three per week) abnormal stool form (hard or loose stool) more than one in every four times abnormal stool passage (straining, urgency, or the feeling of incomplete evacuation) more than one in four times passage of mucus in more than one in every four bowel movements bloating or the sensation of having a distended abdomen on more than one out of every four days.

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Managing IBS

Because there is no cure for IBS, treatment aims to control individual symptoms. As a result, the management of IBS requires a great amount of understanding between doctor and patient. Patients need to educate themselves about IBS and receive adequate information from their physicians so they can learn to manage the syndrome and regain control over their lives.

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Constipation

Constipation is the slow movement of feces through the large intestine, resulting in the difficult passage of dry, hard stool. It's one of the most common gastrointestinal complaints in the United States, responsible for more than 2.5 million visits to health providers each year. The National Institutes of Health says that more than four million Americans have frequent constipation. Constipation is more common in women than men, and more common among older people. Americans spend around $725 million on laxatives each year.

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How constipation happens

The hard, dry stool that defines constipation develops when the colon absorbs too much water. This may happen because the muscle contractions of the colon are too slow, so the stool moves along sluggishly. Or it can occur when the anal sphincter fails to relax when it should, causing an excessive amount of stool to be stored in the rectum. Constipation can also occur when you consciously slow the movement of stool through the colon to hold back a bowel movement. If you routinely override the urge to defecate by consciously constricting the external sphincter muscles that surround the anus, your reflex to defecate may be blunted, and accumulated stool may harden as a result, becoming even more difficult to pass.

Eventually, the colon tries to move the stool by squeezing down to try and push it. This causes an uncomfortable pressure and cramping. If the stool is not eliminated, more hard stool accumulates. When the stool finally passes, it can cause extreme discomfort.

Fast fact On average, Americans eat about 5 to 20 grams of fiber a day, well below the daily 21 to 38 grams recommended by the Institute of Medicine.

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Frequency of bowel movements: What's normal?

What is regularity? It's not a medical concept, but a myth that you've got to move your bowels each day to be healthy. In fact, as far back as 1909, the British physiologist Sir Arthur Hurst said it wasn't unusual to find healthy people who had a bowel movement three times a day or once every three days. Today, that's still the range that's considered "normal." But many perfectly healthy people don't even fall within this broad range. In 1813, the British physician William Heberden described a patient who "never went but once a month." He also described a patient who relieved himself 12 times a day. Both patients seemed perfectly content with their bowel habits.

The truth is that everyone experiences variations in how often they move their bowels. Menstruation, vigorous physical exercise, diet, travel, and stress can all cause temporary changes in bowel habits. Going a day without a bowel movement certainly shouldn't be considered constipation. And three movements in a day isn't necessarily diarrhea. More important than the number of bowel movements is the consistency of the stools as they pass, the effort needed to expel them, any associated symptoms, and changes in frequency.

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Causes of constipation

There are many factors that may predispose someone to constipation. Some can easily be prevented by changing habits and lifestyle (although the role of lifestyle factors in constipation may not be as important as once thought). Often, the cause has to do with physiological problems or diseases. Following are the more common causes of constipation:

Lack of exercise. ? People who exercise regularly seldom complain about constipation. Basically, the colon responds to activity. Good muscle tone in general is important to regular bowel movements. The abdominal wall muscles and the diaphragm all play a crucial role in the process of defecation. If these muscles are weak, they're not going to be able to do the job as well. But exercise is not a cure-all. Increasing exercise to improve constipation may be more effective in older people, who tend to be more sedentary, than in younger people.

Medications. ? Constipation is a side effect of many prescription and over-the-counter drugs. These include pain medications (especially narcotics), antacids that contain aluminum, antispasmodics, antidepressants, tranquilizers and sedatives, bismuth salts, iron supplements, diuretics, anticholinergics, calcium-channel blockers, and anticonvulsants.

Irritable bowel syndrome (IBS). ? Some people who suffer from IBS (see "Irritable bowel syndrome") have sluggish bowel movements, straining during bowel movements, and abdominal discomfort. Constipation may be the predominant symptom, or it may alternate with diarrhea; cramping, gas, and bloating are also common.

Abuse of laxatives. ? People who use laxatives for a long time often come to rely on them for both psychological and physiological reasons. The colon may begin to require laxatives to spur bowel movements. In the past, laxatives were thought to damage nerve cells in the colon and interfere with the colon's innate ability to contract. However, newer formulations of laxatives have made this outcome rare (see "Oral laxatives").

Changes in life or routine. ? Pregnancy, for example, may cause women to become constipated because of hormonal changes or because the heavy uterus pushes on the intestine. Aging often affects regularity because a slower metabolism can reduce intestinal activity and muscle tone. Traveling can give some people problems because it changes normal diet and daily routines.

Ignoring the urge. ? If you have to go, go. If you hold in a bowel movement, for whatever reason, you may be inviting a bout of constipation. People who repeatedly ignore the urge to move their bowels may eventually stop feeling the urge.

Not enough fiber and liquid in the diet. ? A diet too low in fiber and liquid and too high in fats can contribute to constipation. Fiber absorbs water and causes stools to be larger, softer, and easier to pass. Increasing fiber intake helps cure constipation in many patients, but those with more severe constipation sometimes find that increasing fiber makes their constipation worse and leads to gassiness and discomfort.

Other causes of constipation. ? Diseases that can cause constipation include neurological disorders, such as Parkinson's disease, spinal cord injury, stroke, or multiple sclerosis; metabolic and endocrine disorders, such as hypothyroidism, diabetes, or long-term kidney disease; bowel cancer; and diverticulitis (see "Diverticular disease"). A number of systemic conditions, like scleroderma, can also cause constipation. In addition, intestinal obstructions, caused by scar tissue (adhesions) from an operation or strictures of the colon or rectum, can compress, squeeze, or narrow the intestine and rectum, causing constipation.

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Diagnosing constipation

Diagnosing constipation might sound simple, but in order to determine what's causing the problem particularly if it persists your doctor will need to ask questions about your health and symptoms and perform a physical exam. He or she will ask what medications you are taking, in case one of them could be contributing to the problem.

The physical exam may involve a visual and hands-on examination of your abdomen for any masses or tenderness. Your doctor may also perform a digital rectal exam (insertion of a gloved finger into the rectum) to feel for polyps or other abnormalities and to assess the strength of the anal sphincter muscle. He or she may perform one of several tests to help determine if there's a blockage in the colon or an underlying condition such as hypothyroidism.

Among the tests your doctor might order are a fecal occult blood test (FOBT), to determine if there's blood in the stool, or a barium enema and a sigmoidoscopy to look for abnormalities. Patients with functional constipation may need special tests, including a colonic transit study (to measure how quickly stool passes through the colon), defecography (an x-ray of the rectum as barium paste is eliminated), and anorectal manometry (to measure the pressure of anal contraction).

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Treating constipation

People suffering from constipation may try a number of measures, including boosting fiber and fluid intake and increasing physical exercise. Drinking more fluids may reduce the need for the colon to rehydrate stools and is, in any case, harmless. Exercise, which is widely believed to promote regularity (although few studies have investigated this), has many other health benefits as well.

Bowel training is another option. In order to retrain your bowel, you attempt to defecate at a regular time each day, when bowel movements are most likely to occur (first thing in the morning, following exercise, or after a meal, for example). The idea is to repeat the routine until the body adopts the bowel movement as part of its daily rhythm. Although bowel training is harmless and does help some people, it has not been widely tested.

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Diarrhea

Most everyone has had a bout of the runs from eating tainted food or drinking unclean water. But some people experience the frequent, runny bowel movements of diarrhea for no apparent reason. Although diarrhea can accompany a number of GI disorders, both functional and organic, it may occur on its own, intermittently or constantly, for any of several reasons.

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What is diarrhea?

Diarrhea is sometimes defined as having more than three bowel movements a day. But a more widely accepted definition of diarrhea is liquid or watery stools. When diarrhea occurs more than three-quarters of the time and lasts at least three months without an identifiable cause, the diarrhea is said to be functional.

Diarrhea is the body's response to something that upsets the intestines; it's the body's way of clearing out whatever is causing the upset. Sometimes you know exactly what caused the intestinal distress for example, bacterial contamination in food. Other times, it remains a mystery.

In most cases, the problem will clear on its own, and you may not need to call a doctor. Diarrhea usually isn't serious, but it can lead to dehydration and weight loss. And while everybody experiences diarrhea sometimes, for a significant percentage of the population, the condition is persistent. Cases that don't clear up in a few days that is, chronic or functional cases require a doctor's care.

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Causes of diarrhea

Normal defecation depends on the small intestine, colon, rectum, and anal sphincter working normally. In diarrhea, something goes wrong.

The small intestine usually handles about 8 liters of fluid from food and pushes about 1 liter to the colon. The colon absorbs most of this fluid and moves the compacted residue, which contains a few ounces of water, to the rectum. The rectum can store up to 200 grams of stool before defecation is triggered. However, any interference with this process can cause the colon to be overwhelmed by the fluid load, resulting in diarrhea. In fact, any disturbance in the colon that interferes with the packing, storage, or dehydrating of the stool can result in diarrhea.

Diarrhea may be caused by viruses, bacteria, or parasites, as well as by various foods, drugs, and medical conditions or treatments.

Viruses. ? A wide variety of viruses can cause diarrhea (viral gastroenteritis). Among them are rhinovirus or adenovirus, rotavirus (the most common cause of diarrhea in infants), influenza, and norovirus (the most common cause in adults). Most cases are not caused by viruses, although many of the most severe cases are.

Bacteria. Shigella, Vibrio cholerae, Escherichia coli salmonella campylobacter ? A number of bacteria are associated with diarrhea. and produce toxins that cause diarrhea, while and invade the stomach lining and produce inflammation and diarrhea. Food poisoning is usually due to bacterial contamination of food.

Parasites. Giardia intestinalis, Cryptosporidium parvum, Giardia ? Intestinal parasites, such as and roundworms or tapeworms, may cause diarrhea. These parasites are often found in untreated or contaminated water. Drinking untreated water from a lake or stream while camping is a common way to pick up parasites.

Diseases of the bowel. ? Crohn's disease and ulcerative colitis, two forms of inflammatory bowel disease, can cause diarrhea (see "Irritable bowel syndrome: What else could it be?").

Immune deficiency. ? Patients suffering from diseases such as AIDS or those who are undergoing treatments that weaken the immune system and damage the lining of the intestine, such as chemotherapy, may also suffer from severe diarrhea.

Stress. ? Emotions are known to wreak havoc on the bowels in a number of ways. Diarrhea is a common complaint of persons under severe stress or emotional upset.

Foods. ? Certain foods, even if perfectly fresh, can cause diarrhea in some people. Among them are fruits, beans, and coffee. For most people, unripe fruits or any type of spoiled food will cause diarrhea, as will the particular foods that a person cannot tolerate, such as milk products for those who are lactose intolerant.

Medications. Clostridium difficile, C. difficile C. difficile ? A number of drugs, available by prescription and over the counter, can cause diarrhea as a side effect. The most common culprits include antibiotics, antacids containing magnesium, and some blood pressure and heart medications. Because antibiotics kill some of the naturally occurring GI bacteria, the gut becomes more vulnerable to attack by a bacterium that produces toxins that can cause diarrhea. In 2005, the Centers for Disease Control and Prevention reported the emergence of a new, more virulent strain of that causes more serious and more often deadly disease. This strain is not as responsive to treatment with the antibiotic metronidazole, which is normally a first-line therapy for -associated diarrhea.

Do you have diarrhea? According to the Rome III criteria for a diagnosis of diarrhea, patients must have experienced the following for the past three months, with symptoms starting at least six months before diagnosis: loose (mushy) or watery stools without pain occurring in at least three-quarters of stools.

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When to call the doctor

If your diarrhea lasts three days or more, it's time to call the doctor. However, call immediately if there is blood in the stool or if the stool looks like black tar. The same goes for diarrhea accompanied by a fever over 101° F, severe abdominal or rectal pain, and severe dehydration (dry mouth, wrinkled skin, or lack of urination). Weight loss of more than 5 pounds is also a reason to see a doctor.

Chronic diarrhea may be an indication of irritable bowel syndrome, and your doctor may want to evaluate you for that condition. There are forms of chronic diarrhea that have nothing to do with food but are the result of fluids secreted by the intestine. These are called secretory diarrheas and may rarely be caused by hidden tumors, sometimes in the pancreas, that release chemical messengers telling the bowel to release large amounts of liquid. Microscopic colitis is a more common cause of secretory diarrhea. In this case, the colon looks normal during a colonoscopy, but biopsies show intense inflammation of the colon lining.

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Diagnosing diarrhea

The doctor will ask questions about your symptoms and try to determine whether the diarrhea is chronic, or whether it's the result of a virus or bacterium and thus likely to be short-lived. If it's chronic, the doctor will want to probe further to establish whether the diarrhea is due to an organic problem or whether it's functional. You may be asked questions about your habits, including drug or alcohol use. Alcohol abuse commonly results in diarrhea, for example, as does use of certain drugs, including cocaine.

The doctor will probably ask questions such as these:

• When did the diarrhea start?

• Have any other family members been sick?

• Have you recently traveled out of the country?

• Are you having abdominal pain? Fever? Chills?

• Is there blood in the stool?

• Is it worse when you are under stress?

• Do any specific foods make it worse?

• Do you drink coffee? Alcohol?

• What medications are you taking or have you taken recently?

If blood or pus in the stool accompanies diarrhea, or if there is fever, anemia, profound loss of appetite, or severe vomiting, it's not functional diarrhea.

For most people and for most mild episodes of diarrhea, no specific lab tests are required. But for more severe cases, or when symptoms of inflammation are present, the doctor will order stool tests to look for the presence of certain bacteria.

Blood can be drawn to test for hemoglobin, white cell count, and sedimentation rate. A sigmoidoscopy may also be performed. For people over 40, a colonoscopy or a barium enema may be ordered to check for organic diseases. Doctors must exclude the possibility of Crohn's disease, ulcerative colitis, or other serious illness, such as colon cancer. These are usually accompanied by blood in the stool, fever, or weight loss.

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Treating diarrhea

Most people with acute diarrhea will recover on their own; it generally runs its course in a few days. In particularly severe or prolonged episodes, replacement of lost fluids and electrolytes (such as sodium and potassium) is essential to combat dehydration. Clear liquids are the first choice. For mild cases of dehydration, juices, soft drinks, clear broth, and safe water are recommended. Apple juice and sodas are good. Citrus juices are not. Neither are alcoholic beverages.

For more severe cases, sports drinks like Gatorade can replace sugars and electrolytes, but too much may cause further diarrhea. Rehydration solutions such as Pedialyte are probably best, particularly for children with diarrhea.

Products such as kaolin and pectin (Kaopectate) give the stool a firmer consistency. Medications that work to slow the bowel include paregoric, opiates, and diphenoxylate with atropine (Lomotil), all of which are available by prescription only, as well as loperamide (Imodium), which is available over the counter. These provide quick but temporary relief by reducing muscle spasms in the GI tract. They should be used only for a few days, however. Bismuth subsalicylate (Pepto-Bismol) also seems to work pretty well; it may turn the stool and tongue black, so don't be alarmed if that happens.

Be aware, however, that using these remedies for symptomatic relief is controversial, particularly for some types of bacterial gastroenteritis. While they may make you more comfortable, they suppress the diarrhea that helps cast the offending bacteria out of your system. If you slow down the process, the bugs stay in your system longer.

After the first 24 hours, a little food is probably okay. But it may be best to try to go without food as long as possible. If you are really hungry, try going on a BRAT diet: bananas, rice, applesauce, and white toast. The bananas bind the stool, slowing the movement a little. The rice, applesauce, and dry toast are low in fiber and easily digested.

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Preventing diarrhea

Preventing diarrhea is largely a matter of luck and common sense. If certain foods give your intestinal tract a hard time, stay away from them. Many cases of diarrhea are caused by intestinal bugs, but if yours seems to be functional and not connected with bacterial infection, try to assess what conditions seem to trigger it and, in particular, whether stressful situations seem connected. Take steps to reduce stressful situations (see "The Stress Connection") and ask your doctor about medications that might treat functional diarrhea.

General rules for avoiding diarrhea caused by bacterial infections include washing all fruits and vegetables well and making sure they're ripe when you eat them. Rinse chicken before you cook it, and cook chicken and other meats thoroughly. Clean all food preparation areas such as countertops and cutting boards with soap and warm water. Wash your hands thoroughly before and after handling food.

Be careful about eating foods left outside for long periods of time at barbecues or picnics, for example. Bacteria can grow easily in the warm air. And don't take leftovers home from these events. Even inside, leftovers should be refrigerated quickly after the meal has been served.

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Excessive gas

Aside from causing embarrassment, too much gas in the digestive system can result in considerable pain, bloating, and discomfort symptoms that may appear on their own or in conjunction with functional dyspepsia or irritable bowel syndrome. Sometimes, you may even hear and feel air and liquid swirling around inside. But there are practical steps you can take to control this problem.

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Where does gas come from?

There are only two ways for gas to get into the GI tract. Either you swallow it (aerophagia), or it's manufactured in the gut (often producing flatus).

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A gas primer

_{2 2 2 2} The air we breathe is made up mostly of nitrogen (N) and oxygen (O), the gas the human body needs to sustain life. After being swallowed, air enters the GI tract. As it moves along, its makeup changes as oxygen passes into the blood and nitrogen is removed from the blood. Another intestinal gas is carbon dioxide (CO), a byproduct of a chemical reaction with acid in the stomach. Hydrogen (H) is released in the colon when undigested carbohydrates undergo bacterial fermentation.

Bacteria in the gut produce foul-smelling gases when they ferment undigested foods that have not been absorbed in the small intestine. These foods consist mostly of carbohydrates, sugars, and fats. The carbohydrates found in high-fiber foods, such as beans, broccoli, cauliflower, and Brussels sprouts, are the worst culprits. These foods release gases such as methane and hydrogen sulfate, which smells like rotten eggs. The worst odor is related to strong-smelling sulfurs that make up just 1% of flatus.

Methane is detected in about one-third of adults. Studies show that Americans and Europeans are more likely to produce methane than Asians are, possibly because of diet. Women also produce more than men do. Genes may play a role in methane production, as the trait is passed along in families.

₂ Additional carbon dioxide is produced in the colon as the byproduct of bacterial fermentation of unabsorbed sugars and starches. Eating beans will substantially increase CO production, as will taking sodium bicarbonate for heartburn. Thus, it doesn't make sense to use bicarbonate-containing seltzers for gas.

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Diagnosing and treating aerophagia and flatus

The important thing for a doctor to consider in diagnosing a belching, bloating, or flatulence problem is whether it's occurring alone or in conjunction with one or more of the various functional GI disorders or a more serious GI illness. He or she should be alert to problems that may suggest organic disease, such as weight loss or anemia. Of course, a physician may be able to determine quickly that the problem is the result of eating too many beans or swallowing too much air. In most cases, evaluating complaints of gassiness will not require extensive diagnostic testing.

To assess your gassiness, your doctor will first question you about your symptoms and dietary patterns. If upper GI bloating and belching are the major problems, excessive air swallowing may be the culprit. The doctor will ask about possible lactose intolerance as well as habits such as gulping down meals, drinking carbonated beverages, sipping through a straw, chewing gum, smoking cigarettes, or chewing tobacco.

The doctor will also want to know about anxiety and psychological problems that may contribute to air swallowing and predispose people to symptoms, including gas and cramping. Likewise, he or she will want to review the medications you are taking, since some especially drugs that are encapsulated with a sorbitol filler can induce gas, bloating, and diarrhea.

An abdomen distended with air can be detected by listening for a hollow sound when tapped. Organic causes of intestinal distension include obstruction of the bowel or fluid or a mass in the abdomen. But other signs usually accompany these more serious problems, and they usually can be readily confirmed by an imaging study such as a CT scan. Some, such as gastric distension, can be identified with a simple abdominal x-ray. Some doctors may want to run a lactose absorption test or hydrogen breath test to check for lactose intolerance.

Bloating and distension: It's not just excess gas Your abdomen feels uncomfortably full and actually looks a bit larger than usual. Is it just excess gas? That may be part of the explanation, but it's unlikely to be the whole story. That feeling of fullness and tightness in the abdomen is called bloating, while distension is the actual stretching of the abdomen. The two conditions usually occur together, but it is possible to have bloating without distension. Bloating with distension, however, is much more bothersome than bloating alone. Bloating affects 10% to 30% of the general population, with women twice as likely to experience it as men. Functional bloating is an independent diagnosis, but it is also frequently associated with other functional gastrointestinal disorders. For example, 75% of IBS patients complain of bloating; in fact, IBS patients often rank bloating as their most bothersome symptom. Bloating is also often accompanied by excessive flatulence and frequent belching. You might think that bloating and distension would be due to excess gas. But excess gas is not likely to be the only cause of abdominal distension. Here's a case in point: in order to distend the gut by just 2 centimeters, the abdomen must contain 10 times as much gas as normal. In IBS patients, the abdomen distends by an average of 12 centimeters in one day that would mean at least 60 times as much gas as normally would be present if excess gas alone were to blame. So what causes bloating and distension? There is some evidence to suggest that the way the intestine handles gas is impaired in people with bloating and distension. Abdominal wall strength or function may also play a role. For example, abdominal muscles relax during meals to accommodate large volumes of food. In distended patients, the abdominal wall may relax to an abnormally exaggerated degree. Excessive descent of the muscles of the diaphragm, which separates the chest from the abdominal cavity, may also play a role. There are no surefire treatments for bloating and distension. Gradually decreasing the amount of wheat fiber in the diet may reduce symptoms. Use of alpha-galactosidase (Beano), charcoal (which absorbs gas), and simethicone (Gas-X, Phazyme, Mylicon) are not backed by solid evidence, but these products may work, and they are generally considered to be safe. Probiotics have had some success in clinical trials. And in one well-designed study, a 10-day course of the antibiotic rifaximin significantly improved the discomfort of bloating compared with placebo.

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Treating belching

The key here is to reduce the amount of air you swallow. Quitting chewing gum and smoking and maybe trading in loose dentures for snugger ones should cut down on air gulping. One easy fix is to avoid carbonated drinks and whipped desserts, which trigger burping. Some people swear by including certain foods in the diet, such as brown rice or barley broth. Papaya and pineapple are also said to help. Make sure to chew foods slowly, avoid washing food down with liquids, and try to eat smaller meals. And don't eat when you are anxious, upset, or overtired. If you have aerophagia, antidepressants and tranquilizers may calm the nerves or lessen anxiety, but they must be used carefully and only under a doctor's close supervision.

Taking a brisk stroll after eating, rather than taking a nap, is a good idea. It promotes gastric emptying and helps relieve the bloated feeling. When it's time to go to bed, try sleeping on your stomach or right side to aid in the escape of gas and alleviate fullness.

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Treating flatulence

The first step is easy. Stop eating the foods that cause gas: beans, fruits, and other complex carbohydrates, as well as the artificial sweetener sorbitol. But don't eliminate all fruits and vegetables, because these foods are the basis of a healthy diet. A product called Beano, which contains the enzyme alpha-galactosidase, can help metabolize difficult-to-digest complex carbohydrates when taken before meals. And preparations containing the pancreatic enzymes lipase, trypsin, and amylase may reduce gassy emissions by helping to digest proteins, starches, and fats when taken with meals. These enzymes are sold over the counter in capsule form (a product called Super Digestive Enzymes is one example), at stores that sell nutritional supplements.

For some people, a drastic reduction in dietary sugars and some cutback in refined starches and wheat flour may help. Activated charcoal, a tasteless black powder, absorbs gas and for some people cuts down on gassiness, particularly after a high-carbohydrate meal. Occasional use is not harmful. Pepto-Bismol may reduce the odor of flatus.

Some people have had success with anticholinergics, drugs such as dicyclomine (Bentyl) and hyoscyamine (Levsin). These agents block nerves that stimulate the digestive tract. A course of the broad-spectrum antibiotic rifaximin (Xifaxan) may also help reduce flatulence, without side effects.

American Journal of Gastroenterology When all else fails, wearing a deodorizing and absorbing pad containing activated charcoal beneath one's undergarments doesn't stop flatulence, but it can prevent others from noticing it. A 2005 study in the found that such devices are moderately effective.

Table 2: Drugs used to treat functional gastrointestinal disorders
Pregnant or nursing women should not take these drugs, except on the specific advice of a physician.
Antacids
Active ingredient*	Brand name	Use	Side effects	Comments
alumina, aluminum carbonate, aluminum hydroxide	Amphojel, Gaviscon, Maalox, Mylanta	Relieve heartburn and functional dyspepsia pain, and promote ulcer healing by neutralizing stomach acid	Constipation; diarrhea; excessive and prolonged doses may cause bone pain, feeling of discomfort, appetite loss, mood changes, muscle weakness	Side effects more likely for people with kidney disease; aluminum-containing antacids not advised for elderly people with bone disease or Alzheimer's disease; do not use within three to four hours of taking tetracycline-type antibiotics
calcium carbonate	Alka-Mints, Caltrate, Rolaids, Tums	Chalky taste; constipation; excessive and prolonged doses may cause difficult, painful, or frequent urination, appetite loss, mood changes, muscle pain or twitching, nausea, restlessness, unpleasant taste	Side effects more likely for people with kidney disease
magnesia, magnesium carbonate, magnesium hydroxide, magnesium trisilicate	Gaviscon, Gelusil, Maalox, Mylanta, Phillips' Milk of Magnesia	Chalky taste; excessive and prolonged doses may cause difficult or painful urination, dizziness, irregular heartbeat, loss of appetite, mood changes, muscle weakness	Side effects more likely for people with kidney disease; do not use within three to four hours of taking tetracycline-type antibiotics
sodium bicarbonate	Alka-Seltzer, baking soda	Abdominal fullness; belching; excessive and prolonged doses may cause frequent urge to urinate, mood changes, muscle pain, nausea, restlessness	Not advisable for people on low-sodium diets; side effects more likely for people with kidney disease
*Most over-the-counter antacids contain two or more of these active ingredients.

Anticholinergics/Antispasmodics
Generic name	Brand name	Use	Side effects	Comments
atropine with hyoscyamine and phenobarbital	Arco-Lase Plus	Relieve gastrointestinal cramps, spasms	Dry mouth, difficulty urinating or urinary retention, blurred vision, rapid heartbeat, increased ocular tension, headache, nervousness, drowsiness; antispasmodics that contain phenobarbital may cause sedation, drowsiness, or, rarely, agitation	Should not be used by people with glaucoma; a physician should be consulted about concurrent use because these drugs block or boost the actions of many other medications; phenobarbital may decrease the effect of anticoagulants and may be habit-forming
atropine with hyoscyamine, phenobarbital, and scopolamine	Donnatal
dicyclomine	Bentyl
hyoscyamine	Levsin

Antidiarrheal agents
Generic name	Brand name	Use	Side effects	Comments
diphenoxylate and atropine	Lomotil, Logen	Stop diarrhea by slowing down intestinal movement	Abdominal discomfort; constipation; less frequently, may cause blurred vision, urinary discomfort, dry mouth or skin, rapid heartbeat, restlessness, or warm, flushed skin	Drink plenty of fluids; may be habit-forming; not to be used with alcohol or other depressants
loperamide	Imodium, Imodium A-D	Reduce secretion of fluid by the intestine	Abdominal discomfort; constipation; less frequently, may cause drowsiness, dizziness, dry mouth, nausea, vomiting, rash	Drink plenty of fluids; should be used with caution by people with liver disease

2 Histamine H-receptor antagonists
Generic name	Brand name	Use	Side effects	Comments
cimetidine	Tagamet	Relieve heartburn and functional dyspepsia pain and promote ulcer healing by decreasing stomach acid	Rarely, may cause diarrhea, constipation, dizziness, anxiety, depression, drowsiness, sleeplessness, headache, irregular heartbeat, increased sweating, burning, itching, redness of skin, fever, confusion in ill or elderly people	May interfere with the absorption of anticoagulants, antidepressants, and hypertension medications
famotidine	Pepcid	No serious drug interactions known
nizatidine	Axid
ranitidine	Zantac	At high doses may interact with anticoagulants

Laxatives
Generic name	Brand name	Use	Side effects	Comments
docusate	Colace, Surfak	Soften stool by merging with feces and softening consistency	Stomach or intestinal cramps, stomach upset, throat irritation	Generally considered safe for long-term use
mineral oil	various	Soften stool by merging with feces and softening consistency	May cause deficiencies of fat-soluble vitamins if used regularly; can cause lung damage if accidentally inhaled
polyethylene glycol	Miralax	Soften stool and increase the number of bowel movements by flushing the intestine	Upset stomach, bloating, cramping, gas	Considered safe for use during pregnancy
bisacodyl	Correctol, Dulcolax, Fleet, others	Increase the motility of the bowel	Stomach cramps, upset stomach, diarrhea, stomach and intestinal irritation, faintness, irritation or burning in the rectum (from suppositories)	May lead to dependency, have diminished effects with long-term daily use, or cause bowels to lose their normal ability; best used for occasional constipation; may cause a blackening of the lining of the colon seen on colonoscopy, which appears to be harmless
castor oil	Castor oil, Purge	Cause fluid to accumulate in the small intestine	Diarrhea, upset stomach, vomiting, irritation, stomach cramping
senna	Ex-Lax, Fletcher's Castoria, Senokot, others	Increase motility of the bowel	Diarrhea, upset stomach, vomiting, irritation, stomach cramping, pseudomelanosis coli
lubiprostone	Amitiza	Increase the amount of fluid secreted into the bowel, allowing stool to pass more easily	Nausea, diarrhea, bloating, stomach pain, gas, vomiting, heartburn, dry mouth, headache	May be a good option for those not helped by standard treatments

Prokinetic agents
Generic name	Brand name	Use	Side effects	Comments
metoclopramide	Reglan	Enhance gastric emptying	Diarrhea; less frequently, may cause involuntary movement of limbs, restlessness, drowsiness, muscle tremor, spasms, breast discharge	Increases the effects of alcohol and other depressants; caution advised for patients with type 1 diabetes or Parkinson's disease

Proton pump inhibitors
Generic name	Brand name	Use	Side effects	Comments
lansoprazole	Prevacid	Treat reflux esophagitis and promote peptic ulcer healing by suppressing secretion of stomach acid	Rarely, may cause diarrhea, abdominal pain, nausea	May speed the elimination of theophylline; also available as an IV formulation
omeprazole	Prilosec, Zegerid	Rarely, may cause constipation, chest pain, headache, gas, rash, drowsiness	May prolong the effect of other prescription drugs, including diazepam, warfarin, and phenytoin
rabeprazole	Aciphex
pantoprazole	Protonix	Also available as IV formulations
esomeprazole	Nexium

Selective serotonin reuptake inhibitors (SSRIs)
Generic name	Brand name	Use	Side effects	Comments
citalopram	Celexa	Relieve chronic abdominal pain	Upset stomach, diarrhea, vomiting, stomach pain, drowsiness, excessive tiredness, tremor, excitement, nervousness, difficulty falling or staying asleep, muscle or joint pain, dry mouth, excessive sweating, changes in sex drive or ability, loss of appetite	Limited experience in functional bowel disorders. May help close the pain gate in some people.
fluoxetine	Prozac	Rash, headache, dizziness, insomnia, anxiety, drowsiness, excessive sweating, nausea, diarrhea, bronchitis, weight loss, painful menstruation, sexual dysfunction, urinary tract infection, chills, muscle or joint pain, back pain
paroxetine	Paxil	Pain, bodily discomfort, hypertension, sudden loss of strength, rapid heartbeat, itching, nausea, vomiting, weight gain or loss, central nervous system stimulation, depression, vertigo, cough
sertraline	Zoloft	Nausea, trouble sleeping, diarrhea, dry mouth, sexual dysfunction, drowsiness, tremor, indigestion, increased sweating, increased irritability or anxiety, decreased appetite

Serotonin agonists/antagonists
Generic name	Brand name	Use	Side effects	Comments
alosetron	Lotronex	Reduces cramping, abdominal pain, urgency, and diarrhea caused by IBS	Constipation; in rare cases, may cause diarrhea and intestinal bleeding	Available only under a tightly controlled program; only proven effective for women
tegaserod	Zelnorm	Decreases abdominal pain, bloating and constipation caused by IBS; relieve chronic constipation with no known cause	Diarrhea; stomach pain; increased risk of heart attack, stroke, and unstable angina	Available only on a severely restricted basis to women with irritable bowel syndrome or functional constipation who are in critical need of the drug; women must be younger than age 55 and have no pre-existing heart problems

Tricyclic antidepressants
Generic name	Brand name	Use	Side effects	Comments
amitriptyline	Elavil, Endep	Relieve chronic abdominal pain	Dizziness, dry mouth, blurred vision, drowsiness, constipation, urinary retention, hypotension, cardiac arrhythmia	Should not be used with alcohol, other antidepressants, or immediately following a heart attack; side effects may be worse when cimetidine is used simultaneously; caution advised for patients with glaucoma; used at lower doses than for the treatment of depression
desipramine	Norpramine
nortriptyline	Pamelor

Other agents
Generic name	Brand name	Use	Side effects	Comments
activated charcoal	Actidose-Aqua, CharcoCaps	Relieve intestinal gas	Black stools, abdominal pain	Effectiveness uncertain; do not take at the same time as other medications
alpha-galactosidase	Beano	Reduces intestinal gas by breaking down indigestible carbohydrates into digestible sugars	No known side effects	Effectiveness uncertain
bismuth subsalicylate	Pepto-Bismol	Relieves heartburn, indigestion, nausea, diarrhea; occasionally used with antibiotics to cure ulcers	Dark tongue, grayish-black stools; excessive doses may cause anxiety, constipation, dizziness	Avoid if allergic to aspirin or other salicylates
lactase	Lactaid	Relieves gas, abdominal bloating, and diarrhea by breaking down milk sugar into simpler forms that can be absorbed into the bloodstream	No known side effects	Effectiveness uncertain; available as pills or prepared products
rifaximin	Xifaxan	Prevents traveler's diarrhea caused by E. coli; treats small intestine bacterial overgrowth in some IBS patients; reduces flatulence and discomfort of bloating	Headache, constipation, hives and itchiness	Should not be used by people with fever or blood in stool
simethicone	Gas Relief, Gas-X, Mylanta Gas, Phazyme	Relieve pain from excess gas	No known side effects	Effectiveness uncertain

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Glossary

aerophagia: Excessive swallowing of air.

alimentary canal: Another term for the gastrointestinal tract or the digestive tract.

bile: Fluid secreted by the liver that helps break down fats in the small intestine.

chyme: A nearly liquid mass of partly digested food and secretions in the stomach and intestine.

colon: The large intestine.

colonoscopy: Examination of the interior of the colon using a flexible viewing instrument.

diverticula: Finger-shaped pouches protruding off the colon that often develop with age.

diverticulitis: Inflammation of one or more diverticula.

duodenitis: Inflammation of the duodenum.

duodenum: The first part of the small intestine, extending from the stomach to the jejunum.

dysphagia: Difficulty swallowing.

endoscopy: A diagnostic test that allows a physician to view the upper gastrointestinal tract via a flexible tube inserted down the patient's throat.

fecal impaction: An accumulation of hardened stool in the intestine and rectum that makes evacuation impossible.

functional gastrointestinal disorders: Gut ailments whose symptoms cannot be linked to any infection or structural abnormality.

gastritis: Inflammation of the stomach.

ileum: The section of the small intestine between the jejunum and the beginning of the colon.

jejunum: The section of the small intestine between the duodenum and the ileum.

lactose intolerance: The inability of the body to break down lactose; causes gastrointestinal distress.

motility: The ability of the digestive tract to propel its contents.

pepsin: A name for several enzymes secreted by the stomach to break down protein.

peptic ulcer: A raw, crater-like break in the mucosal lining of the stomach or duodenum.

peristalsis: Wavelike movement of intestinal muscles that propels food along the digestive tract.

peritonitis: Inflammation of the membrane lining the abdominal cavity.

sigmoidoscopy: Internal examination of the rectum and sigmoid colon by means of a flexible viewing tube inserted through the anus.

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Resources

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Organizations

Celiac Disease Foundation www.celiac.org 13251 Ventura Blvd., #1 Studio City, CA 91604 818-990-2354

Publishes a quarterly newsletter on celiac disease treatment and nutrition; provides information and referral services.

Celiac Sprue Association www.csaceliacs.org P.O. Box 31700 Omaha, NE 68131 877-272-4272 (toll free)

Provides information and a support system for people with celiac disease; publishes a quarterly newsletter.

Crohn's and Colitis Foundation of America www.ccfa.org 386 Park Ave. S., 17th Floor New York, NY 10016 800-932-2423 (toll free)

Provides books, newsletters, and brochures about Crohn's disease and ulcerative colitis; organizes seminars, medical forums, and public awareness forums. Can refer patients to physicians and self-help groups.

International Foundation for Functional Gastrointestinal Disorders www.iffgd.org P.O. Box 170864 Milwaukee, WI 53217 888-964-2001 (toll free)

Offers information on gastrointestinal disorders; publishes a quarterly newsletter.

Irritable Bowel Syndrome Self-Help and Support Group www.ibsgroup.org 1440 Whalley Ave., #145 New Haven, CT 06515

Provides educational resources and support for people with IBS and other functional GI disorders; publishes a newsletter.

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Books

The Sensitive Gut Harvard Medical School (Simon and Schuster, 2001, 204 pages)

This book is an expanded version of this report, overseen by the same medical editor, Lawrence S. Friedman, M.D. The book addresses more conditions and includes diagnosis, treatment, and self-help information.

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Review Date: 2008-01-01