Senna is an herb that is generally used for its laxative properties. It works by interacting with the bacteria in the digestive tract, resulting in intestinal contractions. These contractions are caused by the anthraquinone that is contained in senna.
It is also used for irritable bowel syndrome (IBS), hemorrhoids and weight loss.
Senna is an herbal laxative that is available without prescription. It is generally safe and well tolerated, but can cause adverse events including clinically apparent liver injury when used in high doses for longer than recommended periods.