Cisapride

Cisapride is a gastroprokinetic agent, a drug which increases motility in the upper gastrointestinal tract. It acts as a serotonin 5-HT4 receptor agonist and indirectly as a parasympathomimetic. Stimulation of the serotonin receptors increases acetylcholine release in the enteric nervous system. It has been sold under the trade names Prepulsid (Janssen-Ortho) and Propulsid (in the U.S.). It was discovered by Janssen Pharmaceutica in 1980. In many countries it has been either withdrawn from the market or had its indications limited because of side effects.

The commercial preparations of this drug are the racemic mixture of both enantiomers of the compound. The (+) enantiomer itself has the major pharmacologic effects and does not induce many of the detrimental side-effects of the mixture.

Clinical uses
Cisapride increases muscle tone in the esophageal sphincter in people with gastroesophageal reflux disease. It also increases gastric emptying in people with diabetic gastroparesis. It has been used to treat bowel constipation.

In many countries it has been either withdrawn or had its indications limited because of reports of the side-effect long QT syndrome which predisposes to arrhythmias. The U.S. Food and Drug Administration (FDA) issued a warning letter to doctors, and cisapride was voluntarily removed from the U.S. market on July 14, 2000.

Veterinary uses
Cisapride is still available in the United States for use in animals and is commonly prescribed by veterinarians to treat megacolon in cats.

Cisapride is also commonly used to treat g.i. stasis in rabbits, sometimes in conjunction with metoclopramide (Reglan).