Loperamide is an antidiarrheal active ingredient available in over-the-counter (OTC) medicines that treat the symptoms of diarrhea, including traveler’s diarrhea. It may be written as loperamide or loperamide hydrochloride (HCl), but it is the same ingredient. Loperamide can be the only active ingredient in an anti-diarrheal medicine or it can be found in medicines that also treat symptoms such as gas.

Loperamide is approved by the U.S. Food and Drug Administration (FDA) and is safe and effective when used according to the Drug Facts label. If you develop abdominal swelling or bulging, or if your diarrhea lasts for more than two days while taking an OTC medicine containing loperamide, contact your healthcare provider. These may be signs of a more serious condition. 

  • You are taking an antibiotic.
  • You have a fever.
  • You have mucus in the stool.
  • You have a history of liver disease.
  • You are pregnant or breastfeeding.
  • You have ever had a rash or other allergic reaction to loperamide.
  • You have bloody or black stool.
  • Your symptoms get worse.
  • Your diarrhea lasts for more than two days.
  • You get abdominal swelling or bulging.
  • You take too much. Immediately contact a healthcare provider or the poison control national helpline at 800.222.1222.
  • Talk to a healthcare provider before giving an OTC containing loperamide to a child under the age of 6.
  • Click here for more information on giving OTCs to children.