What is Senna?
Senna is an herb that contains compounds called anthraquinones, which are powerful laxatives. In fact, the U.S. Food and Drug Administration has approved senna as a nonprescription laxative. Additionally, senna has been found to be effective for cleansing the bowel prior to undergoing colonoscopy (a type of medical procedure widely used in screening for colon cancer) when used in conjunction with other agents.
Health Benefits of Senna Tea
While a number of studies have tested the effects of senna taken in powder or capsule form, very few studies have looked at the potential health benefits of drinking senna tea.
The available research includes a small study published in Investigative Radiology in 2005. For the study, 12 volunteers consumed either senna tea or erythromycin (an antibiotic used to treat certain bacterial infections). While both treatments appeared to increase the movement of stool through the bowels, senna tea appeared to be more effective than erythromycin.
To date, there is no evidence that senna tea can help with detoxification or stimulate weight loss.
Little is known about the safety of long-term intake of senna tea. As such, the National Institutes of Health (NIH) warns against using senna for more than two weeks. Taking senna for longer than two weeks may lead to dysfunction in the bowels, according to the NIH. Additionally, long-term use of senna may increase your risk of muscle weakness, liver damage, and heart function disorders.
Senna Tea and Liver Damage
Long-term excessive consumption of senna tea may be toxic to your liver, according to a 2005 report from the Annals of Pharmacotherapy. The report focused on a 52-year-old woman who ingested one liter of senna tea every day for more than three years and then suffered acute liver failure. The report's authors determined that the patient's liver damage was likely the result of her excessive intake of senna tea.
Senna Tea Side Effects
Although senna is likely safe for most people when used in the short term, it may trigger certain side effects (including stomach discomfort, cramps, and diarrhea).
Who Should Avoid Senna Tea?
If you have any type of heart condition or gastrointestinal disorder (such as Crohn's disease, ulcerative colitis, or inflammation of the stomach), it's crucial to consult your doctor prior to consuming senna or senna tea.
Where to Find Senna Tea
Widely available for purchase online, senna tea can also be found in many natural-foods stores and in stores specializing in dietary supplements.
Using Senna Tea for Health
Due to the lack of supporting research, it's too soon to recommend senna tea as a principal standard treatment for health-related purpose. If you're considering the use of senna tea in treatment of a chronic condition, it's important to talk to your doctor before you begin drinking the tea.
It's also important to note that -- in some cases -- constipation may signal an underlying health problem (such as irritable bowel syndrome or a thyroid disorder). Therefore, self-treating constipation with senna tea and avoiding or delaying standard care may have serious consequences in some cases.
Buhmann S, Kirchhoff C, Wielage C, Mussack T, Reiser MF, Lienemann A. "Assessment of large bowel motility by cine magnetic resonance imaging using two different prokinetic agents: a feasibility study." Invest Radiol. 2005 Nov;40(11):689-94.
National Institutes of Health. "Senna: MedlinePlus Supplements." November 2010.
Vanderperren B, Rizzo M, Angenot L, Haufroid V, Jadoul M, Hantson P. "Acute liver failure with renal impairment related to the abuse of senna anthraquinone glycosides." Ann Pharmacother. 2005 Jul-Aug;39(7-8):1353-7.