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.
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.
- 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 constipation
Medicines for severe constipation that does not improve with home treatment include:
- Lubiprostone (Amitiza), which works by increasing the amount of fluid in your intestines, making it easier for stool to pass.
- Osmotic laxatives (such as Milk of Magnesia and nonabsorbable sugars such as lactulose), which work by holding fluids in the intestine and drawing fluids into the intestine from other tissue and blood vessels. This extra fluid in the intestines makes the stool softer and easier to pass. Use laxatives only when recommended by your doctor.
- Polyethylene glycol (MiraLax), which helps the stool hold on to more water, making it softer and easier to pass.
- Stimulant laxatives (such as Correctol, Dulcolax, or Senokot), which speed up how fast stool moves through the intestines by irritating the lining of the intestines. Regular use of stimulant laxatives is not recommended. Stimulant laxatives change the tone and feeling in the large intestine and you can become dependent on using laxatives all the time to have a bowel movement. Use laxatives only when recommended by your doctor.
For pain and cramping
The following medicines may be used for long-term pain and cramping:
- Anticholinergics (antispasmodics), such as dicyclomine (Bentyl), which help prevent or relieve painful cramping spasms in the intestines
- Antidepressants
For anxiety or depression
The following medications may be used if your IBS causes you to have anxiety or depression:
What To Think About
Few medications have proven consistently helpful and all medications have side effects, so medicine 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, medicine for that illness may be needed.
Alosetron, a medicine 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 medicine 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), the U.S. Food and Drug Administration (FDA) reapproved alosetron for limited use in IBS. Specific guidelines for the use of alosetron require health professionals prescribing it to sign a certificate and patients to sign a consent form.
