Irritable bowel syndrome (IBS) occurs when muscles in your large intestine contract faster or slower than normal. This causes pain, cramping, gassiness, sudden bouts of diarrhea, and constipation.

People may have alternating bouts of constipation and diarrhea, or diarrhea-predominant IBS, or constipation-predominant IBS. Although the symptoms can be hard to live with, IBS does not cause permanent damage to your intestine.

Between 5 to 10% of the population has IBS. IBS peaks between the ages of 20 to 39. But it can occur at any age and is often associated with stress. It affects up to twice as many women as men.

Symptoms of IBS may include:

• Cramping pain in your lower abdomen
• Bloating and gas
• Diarrhea or constipation, or bouts of both
• Immediate need to move your bowels when you wake up, or during or after meals
• Relief of pain after bowel movements
• Feeling of incomplete emptying after bowel movements
• Mucus in your stool

Criteria for an IBS diagnosis include abdominal pain or discomfort for at least 3 days per month for 3 months. Up to 50% of people with IBS have psychological symptoms, such as anxiety and depression. Some people with IBS have low levels of the brain chemical serotonin.

IBS may affect how the body is able to absorb nutrients, so that some people may not be getting all of the nutrients they need.

Researchers do not know what causes IBS, and the intestines of people with IBS appear normal when examined. It may be caused by a disturbance in the muscle movement of the intestine, or a lower tolerance for stretching and movement of the intestine.

Risk factors may include a history of physical or sexual abuse, low-fiber diet, emotional stress, use of laxatives, a bout of infectious diarrhea, or other temporary bowel inflammation.

Diet also plays a major role in IBS. Some doctors believe that food allergies cause some cases of IBS, although studies have been mixed. Fatty foods, artificial sweeteners (sucralose or Splenda and saccharine or Sweet'N Low), chemical additives (dyes and preservatives), red meat, dairy products (such as milk, cheese, and sour cream), chocolate, alcohol, and carbonated beverages (sodas) may trigger or aggravate episodes in some people. Gluten contained in wheat and barley can also be a problem for some people with IBS.

Your doctor will feel your abdomen to check for signs of pain. Other tests may include a rectal exam, pelvic exam (for women), sigmoidoscopy, stool sample testing, blood and urine tests, ultrasound, and x-rays to rule out other conditions.

Doctors may also check to see if you are lactose intolerant. Lactase is an enzyme the body needs to digest sugars found in dairy products. If a person lacks this enzyme, they may have problems digesting dairy products, causing symptoms similar to IBS. Removing milk and dairy products from the diet for several weeks may help determine if the person is lactose intolerant.

The goal of treatment is to relieve symptoms. For some people, changing their diet may reduce symptoms. Adding more fiber and avoiding stimulants, such as caffeine, may help. Reducing anxiety by getting regular exercise and seeking counseling may also be helpful. Alternative and complementary therapies, including herbs, supplements, and lifestyle changes, may help relieve symptoms as well.

Drug Therapies

• Anticholinergic medications. Help relax the muscles in the intestine and relieve pain from bowel spasm. Anticholinergic drugs include hyoscyamine (Levsin and Levsinex) and dicyclomine (Bentyl).
• Antiflatulents. Reduce gas. Antiflatulents include simethicone (Phazyme or Mylicon).
• Antidiarrheal medications. Help decrease and stop diarrhea. Antidiarrheal drugs include loperamide (Imodium) and a combination of diphenoxylate & atropine (Lomotil).
• Fiber supplements, such as psyllium (Metamucil) may help with diarrhea or constipation.
• Antidepressants. May be prescribed to treat pain or depression.

Two drugs are approved specifically to treat IBS. They are used cautiously and only when other treatments have failed.

• Lubiprostone (Amitiza). Increases fluid in the intestine to help speed the passage of stool. It is approved only for women with IBS who predominantly have severe constipation and have failed all other treatments.
• Alosetron (Lotronex). Helps relax the intestine and slow passage of stool. This drug was removed from the market for a while because it was associated with serious side effects. Now it is back on the market, but can only be sold under certain circumstances. Your doctor must be enrolled in a special program to prescribe the drug, and it is approved only for women with IBS who predominantly have diarrhea and have failed all other treatments. Alosetron should not be prescribed for men.

Complementary and Alternative Therapies

IBS is often treated with alternative therapies. Stress reduction techniques, such as biofeedback, hypnosis, dietary changes, or counseling may help.

Nutrition and Supplements

Some doctors believe food allergies trigger IBS, at least for some people. The most common food allergens are dairy products, wheat, corn, peanuts, citrus, soy, eggs, fish, and tomatoes. Your health care provider may recommend an elimination diet, where foods that are suspected of causing an allergic reaction are eliminated from your diet, then gradually added back to see which foods trigger symptoms.

Eating a healthy diet that includes mainly fruits, vegetables, and whole grains may help. If gas is a problem, you may want to avoid beans, cabbage, broccoli, cauliflower, apple juice, grape juice, bananas, nuts, and raisins. These tips may also help:

• Avoid refined foods, such as white breads, pastas, and sugar.
• Eat fewer red meats and more lean meats, cold-water fish, tofu (soy, if no allergy), or beans for protein.
• Use healthy cooking oils, such as olive oil or vegetable oil.
• Reduce or eliminate trans-fatty acids, found in commercially baked goods, such as cookies, crackers, cakes, French fries, onion rings, donuts, processed foods, and margarine
• Take fiber supplements to help reduce pain, cramping, and gas.
• Avoid caffeine, alcohol, chocolate, and tobacco.
• Stay away from sugar substitutes (such as sorbitol and mannitol), which can trigger symptoms in some people.
• Drink 6 to 8 glasses of filtered water daily.
• Exercise 30 minutes daily, 5 days a week.
• Engage in regular, stress-relieving activities, such as meditation and yoga.

These supplements may also help relieve IBS symptoms:

• Probiotic supplement (containing Lactobacillus acidophilus and Bifidobacterium). Probiotics, or "friendly" bacteria, help your digestive system function properly. Many studies show that probiotics help relieve symptoms of IBS, including abdominal pain, gas, and constipation. Some probiotic supplements need refrigeration for best results. Check the label carefully. People who are severely immunocompromised, or who are taking immune-suppressing drugs, should check with their physicians before taking a probiotic supplement.
• Flaxseed. To relieve constipation. One study of 55 people with constipation caused by IBS found that those who took used flaxseed reduced constipation, boating, and abdominal discomfort more than those who used psyllium. Start slowly with flaxseed and add more gradually, under your doctor's guidance.
• Melatonin. A few small studies have suggested melatonin may improve IBS symptoms. Ask your health care provider about potential drug interactions before taking melatonin.

Herbs

You can use herbs in the form of dried extracts (such as capsules, powders, and teas), glycerites (glycerine extracts), or tinctures (alcohol extracts). Herbs have active ingredients that can interact with other herbs, supplements, or medications. Speak to your doctor if you are taking any medications, or if you have underlying medical conditions. Unless otherwise indicated, make teas with 1 tsp. herb per cup of hot water. Steep covered 5 to 10 minutes for leaf or flowers, and 10 to 20 minutes for roots.

• Peppermint oil (Mentha piperita). Peppermint oil is used traditionally for digestive problems, and some studies show it may help relieve symptoms of IBS, including gas and cramping. In one study, peppermint oil combined with 50 mg of caraway oil in enteric-coated capsules taken 3 times daily reduced IBS symptoms. Peppermint can potentially interact with medications. Speak with your physician.
• Chinese herbal medicine. In one study, a standardized Chinese herbal extract containing 20 herbs, including dan shen (Salvia miltiorrhiza), ginger (Zingiber officinale), wormwood Artemesia absinthium), and bupleurum, helped reduce symptoms of IBS. All of these herbs can potentially have side effects and/or drug interactions. If you are interested in using Chinese herbal medicine for IBS, consult a knowledgeable health care provider to make sure you get the safest and most effective formula for you.

Homeopathy

Few studies have examined the effectiveness of specific homeopathic remedies. Professional homeopaths, however, may recommend treatments for IBS based on their knowledge and clinical experience. Before prescribing a remedy, homeopaths take into account a person's constitutional type, includes your physical, emotional, and intellectual makeup.

Acupuncture

Several small studies suggest that acupuncture may help people who have IBS by improving general well being and reducing bloating. More research is needed.

Acupuncturists treat people with IBS based on an individualized assessment of the excesses and deficiencies of qi located in various meridians. In the case of IBS, an acupuncturist usually detects a qi deficiency in the spleen and lung meridians. Acupuncturists frequently use moxibustion (a technique in which the herb mugwort is burned over specific acupuncture points) for treatment of IBS because they believe its effects reach deeper into the body. Because acupuncture is considered safe, and IBS is not easily treated by available conventional methods, people with IBS may wish to try acupuncture therapy to improve symptoms.

Chiropractic

There have been no well-designed studies of chiropractic for IBS. However, chiropractors report that spinal manipulation may improve symptoms of IBS in some people. In these cases, spinal manipulation may have a balancing effect on the nerves that supply impulses to the intestinal tract.

Other Treatments

• Electric heating pads, hot water bottles, and long hot baths can relieve painful spasms and cramping in the abdomen.
• Regular exercise, such as walking, can reduce stress and encourage bowel movements if you are constipated. One study of IBS patients found that those who exercised regularly had fewer IBS symptoms than those who did not.
• Castor oil packs can soothe cramping muscles and aid detoxification. Apply oil directly to skin, cover with a clean soft cloth and plastic wrap. Place a heat source over the pack, and let it sit for 30 to 60 minutes. Never use castor oil internally, and do not use castor oil packs more than 3 days per week unless directed to do so by your physician.
• Deep breathing reduces stress and may also help with digestion.
• Therapeutic massage may help reduce stress.
• Preliminary research suggest that yoga may help relieve pain and other symptoms of IBS.
• Stress reduction techniques, such as hypnosis, biofeedback, or counseling, may also help.

IBS may cause stress. Following a diet recommended by your doctor is very important.

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