Antidiarrheal agents

In irritable bowel syndrome (IBS) patients with diarrhea, an antidiarrheal agent such as loperamide is a drug which slows gut transit.

Transit refers to the amount of time it takes for materials to move through the gut. These also decrease intestinal secretion (movement of fluid into the intestines) and increase the amount of fluid that is reabsorbed by the gastrointestinal (GI) tract. 

Loperamide (e.g., Imodium, Pepto Diarrhea Control) is available over-the-counter (OTC) and is the most commonly used antidiarrheal. This drug works by bonding to μ-opioid receptors in the GI tract resulting in the changes mentioned above. Similar to OTC laxatives, a few studies have shown that it solidifies loose stools and reduces the frequency of diarrhea. However, it has not been shown to have a beneficial effect on abdominal pain or discomfort. Side effects associated with Loperamide include abdominal pain and constipation which can become severe. Discontinue use if constipation develops and be sure to contact your healthcare provider. 

Be sure to take any medication as directed. Always tell your health care professionals about all the medicines you are taking, including OTC and prescription medicines.

Learn more about long-term use of loperamide

Last modified on October 22, 2014 at 01:51:25 PM

Adapted from IFFGD Publication #168 “Current Pharmacologic Treatments for Adults with Irritable Bowel Syndrome”. By: Darren M. Brenner, MD, Associate Professor of Medicine and Surgery, Northwestern University – Feinberg School of Medicine, Chicago, Illinois; Adapted from an article by: Tony Lembo, MD, Professor, of Medicine and Rebecca Rink MS, Beth Israel Deaconess Medical Center, Harvard Medical School, MA; Edited by: Lin Chang, M.D., Professor of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA

Share this page
Share on facebook
Share on twitter
Share on linkedin
Share on email
Share on print
Topics of this article
Was this article helpful?

IFFGD is a nonprofit education and research organization. Our mission is to inform, assist, and support people affected by gastrointestinal disorders.

Our original content is authored specifically for IFFGD readers, in response to your questions and concerns.

If you found this article helpful, please consider supporting IFFGD with a small tax-deductible donation.

Related Information
Personal Stories
Skip to content