Learning About Melanosis Coli

Melanosis coli is a harmless condition that makes the lining of the colon discolored. It's not a life-threatening health problem. It's not cancer. Instead of a pinkish color, the colon wall looks dark brown or black. Melanosis coli causes no...

What is melanosis coli?

Melanosis coli is a harmless condition that makes the lining of the colon discolored. It's not a life-threatening health problem. It's not cancer. Instead of a pinkish color, the colon wall looks dark brown or black.

What are the symptoms?

Melanosis coli causes no symptoms. It's most often found during a colonoscopy exam.

What causes it?

Melanosis coli is most often caused by long-term (chronic) use of plant-based laxatives. Laxatives that use plants such as senna, rhubarb, cascara, and aloe are more likely to cause it. As the laxative passes through the colon, it can damage cells in the lining of the colon. This can lead to cell death. When the cells die, they create a dark pigment that stains the lining. The change in color of the colon wall can start after just a few months of chronic laxative use. Chronic colitis may also cause it.

How is it diagnosed?

Melanosis coli is found during a colonoscopy that is done for other health reasons. Usually a small sample or biopsy is taken of the discolored colon tissue. This is done to make sure it's not caused by some other health problem. Your doctor will ask about your health history. The doctor may also ask about any medicines you are taking. This includes over-the-counter medicines and herbal supplements and teas.

How is it treated?

If melanosis coli is caused by a laxative you're taking, your doctor may have you stop taking it. This usually stops the condition. But it can take up to a year for the colon wall to return to its normal color.

If you still have constipation, your doctor may suggest other options. These include osmotic laxatives or fiber supplements. These don't cause a color change in the colon. Your doctor may also talk to you about making changes to your diet that can help. These may include eating foods that are rich in fiber and drinking more water. Limiting alcohol can also help.

Your doctor may suggest other lifestyle changes, such as getting enough sleep and being more active. The doctor can also look at any medicines you are taking to see if they are the cause of your bowel problems.