Loperamide Hydrochloride is an anti-diarrhea drug which provides relief of diarrheal symptoms, resulting from nonspecific diarrhea or inflammatory bowel disease. It is often marketed as the following products: Lopex, Maalox, Imodium A-D, Kaopectate, and Pepto Diarrhea Control.

It works by increasing the tone of the large intestine causing contents to move more slowly through. As a result, feces remains for an extended period of time in the intestine. This produces a lessening of stool volume, increased stool viscosity, and decreased fluid loss.

It is an opioid and acts on the opioid receptors in the large intestines; it does not affect the central nervous system like other opioids.

Treatment is not recommended for patients who should avoid constipation and for diarrhea associated with organisms that can penetrate the intestinal walls, such as E. Coli or Salmonella. Treatment should also be avoided if body temperature exceeds 101 degrees Fahrenheit or stool is bloody.

Side effects can include the following: constipation, abdominal pain or discomfort, dry mouth, fatigue, and in rare cases toxic megacolon.