Antidiarrheal medicines, such as atropine and diphenoxylate
(such as Lomotil), eluxadoline (such as Viberzi), and loperamide (such as Imodium), slow intestinal movements.
This allows stool to stay in the intestine longer, allowing more water to be
absorbed, which makes the stool formed rather than watery when it is
passed. Antidiarrheals can help with diarrhea in IBS.footnote 1
Atropine and diphenoxylate may cause dry skin, itching, dizziness, drowsiness,
nausea, or vomiting. Psychological dependence may occur in high doses.
Loperamide may cause abdominal (belly) pain, dry mouth, nausea, vomiting, or
dizziness. These side effects are usually minor and do not last long. This
medicine may not help people who have alternating periods of diarrhea and
constipation, because it may make the constipation worse.
These medicines may be dangerous if they are used by people who
have certain types of intestinal infections or who have
inflammatory bowel disease. You should not use these
medicines if you have a fever or if you have blood in your stool.
See Drug Reference for a full list of side effects. (Drug Reference
is not available in all systems.)
American College of Gastroenterology (2009). An evidence-based systematic review on the management of irritable bowel syndrome. American Journal of Gastroenterology, 104(Suppl 1): S8–S35.