The colon, or large intestine, is an essential organ for absorbing nutrients, synthesizing vitamins and regulating water levels in the body. Lack of a well balanced diet, especially foods high in fiber, can lead to clogging of the colon. Clogging, or impacting of the colon can cause a host of symptoms, including malabsorption, blood toxicity, vitamin deficiencies, constipation, abdominal pain and lack of energy. Senna is a powerful herbal laxative that promotes bowel movements, although it's not necessarily the best remedy to use for a colon cleanse.
A healthy colon should produce two well-formed bowel movements daily, which take no effort and do not contain mucous, blood or partially digested food. However, the typical American diet contains far less fresh fruits and vegetables, and much more refined carbohydrates and preservatives, which reduces intestinal movement and leads to sticky fecal matter. Sticky feces coat the membranes of the colon and compact into the natural folds of the lumen, reducing absorption and causing decay and toxicity. A complete colon cleanse includes irrigation, which is referred to as a colonic, and involves flushing-out the large intestine with pressurized warm water. However, most colon cleaners are over-the-counter supplements that contain herbal laxatives, such as senna.
Senna, or Cassia acutifolia, is a plant indigenous to China, India and other parts of Asia and considered part of the bean family. Senna leaves and seeds are used medicinally because they are a rich source of anthroquinone glycosides, which stimulate the bowel to contract, creating a strong laxative effect, as cited in “The Way of Chinese Herbs.” Senna is an ingredient in the commercial laxative, Ex-Lax, which is widely used to relieve constipation. Herbalists consider senna as a powerful natural laxative and not nearly as gentle as other herbs that contain anthaquinones, such as cascara sagrada, but not the best choice for cleansing the colon because of its many side effects, “The Essential Book of Herbal Medicine" states. Bowel movements usually occur from six to twelve hours after taking senna, which is available in tea bags, capsules, tablets and liquid extracts.
Side effects of senna include strong abdominal cramps and pains, intestinal irritation, bloating, nausea, diarrhea, electrolyte imbalance, body swelling, discolored urine and staining of the colon, called melanosis coli. Senna can also be habit-forming, which is why small amounts are recommended over short periods of time, such as a week or less. A colon dependent on the effects of senna may become “lazy” and be less active with peristalsis, or contractions, which is what causes food to move toward the rectum. Furthermore, senna may interact with drugs called calcium channel blockers, and has been linked to liver toxicity and colorectal growths in large dosages. In short, senna is a potent herb for constipation, but should be considered as a last resort.
Due to its powerful effects, senna or other herbs containing anthraquinones should be avoided by people with diverticulitis of the colon, ulcerative colitis, Crohn's disease, severe hemorrhoids, congestive heart disease, abdominal hernias, gastrointestinal cancer, recent colon surgery, or any liver and kidney condition, warns “Medical Herbalism: The Science Principles and Practices of Herbal Medicine.” Pregnant women and children are also advised not to use senna.