A Case of Primary Melanoma of the Transverse Colon Cureus Melanosis coli** Melanosis coli is a benign, reversible condition characterized by brown black pigmentation of the colonic mucosa, most often due to chronic use of anthraquinone laxatives. The discoloration is caused PT 141 Nasal Spray for Women for Sexual Arousal and Libido Enhancement PT 141 Bremelanotide Nasal Spray SweetSpot Labs USA Leopard skin appearance on colonoscopy. Melanosis coli is a condition characterized by dark brown or black pigmentation of the colon lining, often resulting from the prolonged use of anthraquinone laxatives like senna “Melanosis” in the small and large intestine