There are many claimed benefits of senna. The herbal product is said to be useful for treating irritable bowel syndrome, promoting weight loss, and various other conditions. Although senna (in the form of sennosides) has been shown to be effective for treating constipation and for preparing the bowel for colonoscopies or other similar procedures, not much evidence is available to support other uses of the product.
Senna is claimed to be beneficial for a few different purposes. Some of these uses include:
- Treating constipation (as a stimulant laxative)
- Treating irritable bowel syndrome (IBS)
- Preparing the bowels for a colonoscopy or other diagnostic or screening procedures (as part of "bowel prep")
- Preventing pain due to straining in people with hemorrhoids or anal fissures
- "Cleansing" the colon
- Promoting weight loss.
Senna (in the form of sennosides in non-prescription medications) is approved only for the treatment of constipation or (for some products) for preparing the bowel for a colonoscopy or other similar procedure. There is less evidence that it is effective for other uses. In any case, senna should be used for short-term use only and is never appropriate as a weight loss aid (see Is Senna Safe? for more information).
If stool softening is also desired, combination products with both senna and docusate (a stool softener) are also available.
Senna contains sennosides, compounds that act as a stimulant laxative. It is thought that senna works by irritating the lining of the digestive tract, which causes fluid secretion and helps stimulate movement through the colon. It has also been suggested that senna may work by affecting prostaglandins or serotonin in the digestive tract.