What is the role of prokinetic agents for constipation?
Adult constipation: The options are limited
One RCT of cisapride for constipation showed that it improved symptoms,5 whereas another demonstrated no significant difference between cisapride and placebo in constipation-predominant irritable bowel syndrome.6 Reports of fatal arrhythmias have prompted restrictions on the use of the drug.
In 2 RCTs of tegaserod for constipation, patients exhibited improved abdominal symptoms and increased spontaneous bowel movements (NNT=6 for 2 mg and 5 for 6 mg in the first study; NNT=11 for 2 mg and 7 for 6 mg in the second study).7,8 A pooled analysis of RCTs of tegaserod revealed an increase in cardiovascular events, prompting withdrawal of the drug from the market (number needed to harm=1000).9 Tegaserod is available only for emergency and investigational use.
,Renzapride, a newer prokinetic similar to cisapride, is under investigation. It is one tenth the strength of cisapride and carries a lower potential risk of cardiac complications.10 Two small placebo-controlled trials demonstrated improved abdominal pain and stool consistency, but only 1 showed statistically significant results compared with placebo.11,12
Recommendations
The North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition states that the benefits of cisapride do not outweigh the risks.13 The American College of Gastroenterology’s Chronic Constipation Task Force states that tegaserod effectively treats chronic constipation.14 Neither guideline includes recommendations regarding other prokinetic agents.
