Melanosis coli is dark brown black pigmentation of colorectal mucosa associated with chronic use of laxatives containing anthraquinone. Examples of such laxatives include senna and rhubarb derivatives. Clinical Importance: There is no association ICD 10 CM TRAINING July 16, 2013 MELANOSIS COLI** Melanosis coli is a disorder of pigmentation of the bowel wall. Histology demonstrates pigment laden macrophages It is associated with laxative abuse, especially **anthraquinone compounds such as senna** Melanosis coli Wikipedia Medical Coding Crohn's Disease Coding Clarified