loperamide, Imodium A-D, Anti-Diarrheal, TH Anti-Diarrheal, Diamode, Imodium, Kaopectate II, Imodium

  • Medical Author:
    Omudhome Ogbru, PharmD

    Dr. Ogbru received his Doctorate in Pharmacy from the University of the Pacific School of Pharmacy in 1995. He completed a Pharmacy Practice Residency at the University of Arizona/University Medical Center in 1996. He was a Professor of Pharmacy Practice and a Regional Clerkship Coordinator for the University of the Pacific School of Pharmacy from 1996-99.

  • Medical and Pharmacy Editor: Jay W. Marks, MD
    Jay W. Marks, MD

    Jay W. Marks, MD

    Jay W. Marks, MD, is a board-certified internist and gastroenterologist. He graduated from Yale University School of Medicine and trained in internal medicine and gastroenterology at UCLA/Cedars-Sinai Medical Center in Los Angeles.

What is loperamide, and how does it work (mechanism of action)?

Loperamide is a medication that is used for the relief of acute diarrhea and the management of chronic diarrhea in patients with inflammatory bowel disease (Crohn's disease and ulcerative colitis). The effectiveness of loperamide is comparable to another anti-diarrheal, diphenoxylate (Lomotil). Loperamide reduces diarrhea by slowing the forward propulsion of intestinal contents by the intestinal muscles. Although loperamide is related chemically to narcotics such as morphine, it does not have any of narcotics' pain- relieving effects even at high doses. Loperamide was approved by the FDA in 1976.

What brand names are available for loperamide?

Imodium A-D, Anti-Diarrheal, TH Anti-Diarrheal, Diamode

Is loperamide available as a generic drug?


Do I need a prescription for loperamide?

Yes, but also OTC

What are the side effects of loperamide?

Loperamide is generally well-tolerated. The side effects that have been reported during loperamide treatment include:

Quick GuideInflammatory Bowel Disease (IBD) Causes, Symptoms, Treatment

Inflammatory Bowel Disease (IBD) Causes, Symptoms, Treatment

What is the dosage for loperamide?

In adults and children 12 years of age and older, the usual dose is 4 mg initially, followed by 2 mg after each loose stool. The maximum dose is 16 mg/day (8 mg if self medicating).

For chronic diarrhea 4-8 mg per day may be administered after control is achieved.

The dose for acute diarrhea in children is: age 8 to 12 years, 2 mg three times the first day; age 6 to 8 years, 2 mg twice the first day; age 2 to 5 years, 1 mg three times the first day. After the first day, children less than 12 years of age usually receive a dose of 0.1 mg/kg after a loose stool.

Chronic diarrhea in children is treated with 0.08-0.24 mg/kg/d divided into two doses, one dose given every 12 hours. For traveler's diarrhea children 6-12 years old receive 2 mg after the first lose stool then 1 mg after each subsequent stool. Children older than 12 receive 4 mg initially then 1 mg after each loose stool.

The maximum daily dose for traveler's diarrhea is 4 mg (6-8 years old), 6 mg (6-12 years old), and 8 mg (>12 years old).

Which drugs or supplements interact with loperamide?

Cholestyramine (Questran) binds to loperamide in the intestines and prevents its absorption, thereby reducing the effect of loperamide. Therefore, there should be at least a two hour interval between doses of loperamide and cholestyramine. Some drugs which are used to increase propulsion of intestinal contents theoretically could counteract loperamide. Such drugs include bethanechol (Urecholine), cisapride (Propulsid), metoclopramide (Reglan), and erythromycin.

Is loperamide safe to take if I'm pregnant or breastfeeding?

There are no adequate studies of loperamide in pregnant women. However, studies in animals receiving very high doses of loperamide suggest no important, detrimental effects on the fetus. Physicians may use loperamide during pregnancy if its benefits are deemed to outweigh the potential but unknown risks.

It is not known if loperamide is secreted in breast milk.

What else should I know about loperamide?

What preparations of loperamide are available?

Capsules or tablets: 1 or 2 mg; liquid: 1 mg per teaspoonful (5 ml).

How should I keep loperamide stored?

Loperamide should be stored at room temperature, 15 C - 30 C (59 F - 86 F).

Reference: FDA Prescribing Information


Loperamide (Imodium; Kaopectate II; Imodium A-D; Maalox Anti-Diarrheal) is prescribed for the relief of acute, chronic, or traveler's diarrhea. Side effects, drug interactions, warnings and precautions, pediatric and pregnancy information should be reviewed prior to taking this medication.

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See more info: loperamide on RxList
Reviewed on 2/24/2015
Reference: FDA Prescribing Information

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