Melanosis Coli (cont.)

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What are the symptoms of melanosis coli?

Melanosis coli does not cause symptoms.

What causes melanosis coli?

Melanosis coli usually results from chronic use of laxatives of the anthranoid group. Some examples of anthranoid laxatives are senna (sennosides; Senocot, Senokot EXTRA and others) and rhubarb derivatives. Many of these laxatives have been in use for hundreds of years. In 1997, the U.S. Food and Drug Administration (FDA) banned the use of the popular anthranoid laxative phenolphthalein due to fears that it might be carcinogenic (cancer-causing). Animal studies had shown that extremely high doses of phenolphthalein led to tumors in animals, but it has never been shown to cause cancers in humans.

The anthranoid laxatives pass through the gastrointestinal tract unabsorbed until they reach the large intestine, where they are changed into their active forms. The resulting active compounds cause damage to the cells in the lining of the intestine and leads to apoptosis (a form of cell death). The damaged (apoptotic) cells appear as darkly pigmented bodies that may be taken up by scavenger cells known as macrophages. When enough cells have been damaged, the characteristic pigmentation of the bowel wall develops. The condition can develop after just a few months of laxative use.

How is melanosis coli diagnosed?

Melanosis coli can be observed during endoscopic procedures that examine the large intestine, such as colonoscopy and sigmoidoscopy . Sometimes the diagnosis is made upon microscopic examination of biopsies taken during endoscopic procedures.

Medically Reviewed by a Doctor on 7/17/2014

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Melanosis Coli - Symptoms and Diagnosis Question: What symptoms, if any, did you experience with melanosis coli, and how were you diagnosed?