Irritable Bowel Syndrome (IBS) - Medications

Medications

Medication may be used along with lifestyle changes to manage symptoms of irritable bowel syndrome (IBS).

The goal of medication treatment is to relieve your symptoms enough to prevent them from interfering with your daily activities, because it may not be possible to eliminate your symptoms. Medications may be prescribed to treat moderate to severe pain, diarrhea, or constipation that does not respond to home treatment. No single medication has been shown to be effective in relieving IBS over the long term.

• Antidepressant medications may improve IBS symptoms even in people who do not have depression, especially the medication class known as tricyclic antidepressants. Antianxiety medications may help if anxiety contributes to your IBS symptoms.
• Alosetron, a medication that decreases abdominal sensitivity, has been shown to relieve symptoms in some women who have severe diarrhea and who have not responded to other treatments. Although this medication was previously removed from the market when its use was shown to contribute to ischemic bowel disease (which occurs when there is not enough blood flowing to the intestines), alosetron has recently been approved by the U.S. Food and Drug Administration (FDA) for reintroduction. Specific guidelines for the use of alosetron require health professionals prescribing it to sign a certificate and patients to sign a consent form.³

Medication Choices

In most cases, the choice of medication is based on your most troublesome symptom. For example, if diarrhea is the most bothersome symptom, using antidiarrheals or anticholinergics may be helpful.

For diarrhea

Medications that may be used to treat severe diarrhea that does not improve with home treatment include:

• Antidiarrheals, such as diphenoxylate (Lomotil) and loperamide (Imodium), which slow intestinal movements.
• Bile acid binding agents (cholestyramine), which prevent bile acids from stimulating the colon, slowing the passage of stools and relieving diarrhea.
• Anticholinergics (antispasmodics), such as dicyclomine (Bentyl), which help prevent or relieve painful cramping spasms in the intestines.
• Alosetron (Lotronex), which is used for some women who have severe diarrhea and who have not responded to other treatments. This medicine slows the movement of stools through the bowels.

For pain with anxiety or depression

The following medications may be used if long-term (chronic) pain also occurs with anxiety or depression:

• Antidepressants
• Antianxiety agents (benzodiazepines)

Other

Additional medications are being studied to treat IBS. They are not yet available for use in the United States. Medications to relax smooth muscle to reduce abdominal pain and bloating include darifenacin, pinaverium, and trimebutine. Trimebutine is available in Canada. Both pinaverium and trimebutine are available in Europe.

What To Think About

Since few medications have proven consistently helpful and because all medications have side effects, medication should be used for specific symptoms that disrupt your normal daily activities.

If you also have another illness, such as depression, that triggers symptoms of irritable bowel syndrome, medication treatment for that illness may be needed.

In March 2007, the U.S. Food and Drug Administration (FDA) announced that the makers of tegaserod (Zelnorm) agreed to stop selling it because of a higher risk of heart attack, stroke, and chest pain. Tegaserod (Zelnorm) was used to treat chronic constipation and irritable bowel syndrome. If you have IBS with constipation and if other medicines have not helped your symptoms, you may be able to try Zelnorm. The FDA has allowed this medicine to be prescribed as part of a restricted-use program. Talk with your doctor to see if you may be able to try Zelnorm.