Senna is the fruit (pod) or leaf of the plant Senna alexandrina. It is approved in the US as a laxative for short-term treatment of constipation.

Senna contains many chemicals called sennosides. Sennosides irritate the lining of the bowel, which causes a laxative effect.

People also use senna for irritable bowel syndrome (IBS), hemorrhoids, weight loss, and many other conditions.