loperamide, Imodium; Kaopectate II; Imodium A-D; Maalox Anti-Diarrheal

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GENERIC NAME: loperamide

BRAND NAMES: Imodium, Kaopectate II, Imodium A-D, Maalox Anti-Diarrheal Caplets, Pepto Diarrhea Control

DRUG CLASS AND MECHANISM: 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.

PRESCRIPTION: Yes, but also OTC

GENERIC AVAILABLE: Yes

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

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

PRESCRIBED FOR: Loperamide is used for the relief of acute or chronic diarrhea and traveler's diarrhea.

DOSING: 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).

DRUG INTERACTIONS: 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.

PREGNANCY: 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.

NURSING MOTHERS: It is not known if loperamide is secreted in breast milk.

 SIDE EFFECTS: Loperamide is generally well- tolerated. The side effects that have been reported during loperamide treatment include abdominal pain, constipation, drowsiness, dizziness, dry mouth, fatigue, nausea, and vomiting.

Reference: FDA Prescribing Information


Last Editorial Review: 3/1/2012




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