Treatments and drugs

By Mayo Clinic Staff

Because it's not clear what causes irritable bowel syndrome, treatment focuses on the relief of symptoms so that you can live as normally as possible.

In most cases, you can successfully control mild signs and symptoms of irritable bowel syndrome by learning to manage stress and making changes in your diet and lifestyle. But if your problems are moderate or severe, you may need to do more. Your doctor may suggest:

  • Fiber supplements. Taking fiber supplements, such as psyllium (Metamucil) or methylcellulose (Citrucel), with fluids may help control constipation.
  • Anti-diarrheal medications. Over-the-counter medications, such as loperamide (Imodium), can help control diarrhea.
  • Eliminating high-gas foods. If you have bothersome bloating or are passing considerable amounts of gas, your doctor may suggest that you avoid such items as carbonated beverages, salads, raw fruits and vegetables — especially cabbage, broccoli and cauliflower.
  • Anticholinergic medications. Some people need medications that affect certain activities of the autonomic nervous system (anticholinergics) to relieve painful bowel spasms. These may be helpful for people who have bouts of diarrhea, but can worsen constipation.
  • Antidepressant medications. If your symptoms include pain or depression, your doctor may recommend a tricyclic antidepressant or a selective serotonin reuptake inhibitor (SSRI). These medications help relieve depression as well as inhibit the activity of neurons that control the intestines. If you have diarrhea and abdominal pain without depression, your doctor may suggest a lower than usual dose of tricyclic antidepressants, such as imipramine (Tofranil) and amitriptyline. Side effects of these drugs include drowsiness and constipation. SSRIs, such as fluoxetine (Prozac, Sarafem) or paroxetine (Paxil), may be helpful if you're depressed and have pain and constipation. These medications can worsen diarrhea, however.
  • Antibiotics. It's unclear what role, if any, antibiotics might play in treating IBS. Some people whose symptoms are due to an overgrowth of bacteria in their intestines may benefit from antibiotic treatment. But more research is needed.
  • Counseling. If antidepressant medications don't work, you may have better results from counseling if stress tends to worsen your symptoms.

Medication specifically for IBS

Two medications are currently approved for specific cases of IBS:

  • Alosetron (Lotronex). Alosetron is a nerve receptor antagonist that's designed to relax the colon and slow the movement of waste through the lower bowel. The drug was removed from the market soon after its original approval because it was linked to serious complications. The Food and Drug Administration (FDA) has since allowed alosetron to be used again — with restrictions. The drug can be prescribed only by doctors enrolled in a special program and is intended for severe cases of diarrhea-predominant IBS in women who haven't responded to other treatments. Alosetron is not approved for use by men.

    Generally, alosetron should only be used if usual therapy for IBS has failed. Additionally, it should only be prescribed by a gastroenterologist with expertise in IBS because of the potential side effects.
  • Lubiprostone (Amitiza). Lubiprostone is approved for adult women and men who have IBS with constipation. Lubiprostone is a chloride channel activator that you take twice a day. It works by increasing fluid secretion in your small intestine to help with the passage of stool. Common side effects include nausea, diarrhea and abdominal pain. More research is needed to fully understand the effectiveness and safety of lubiprostone. Currently, the drug is generally prescribed only for those with IBS and severe constipation for whom other treatments have failed.
Jul. 29, 2011