Melanosis, or black change disease of the colon, can be relieved on its own after eliminating the causative factors and does not require special treatment. Colonic melanosis is a non-inflammatory bowel disease characterized by dark pigmentation of the colonic mucosa, mostly triggered by long-term use of anthraquinone laxatives, and patients may experience abdominal distension, constipation, anal swelling, increased flatulence, and other uncomfortable symptoms. The disease is a benign lesion, generally eliminate the causative factors (such as stop using anthraquinone laxatives) after the condition can be slowly self-healing, constipation is serious can be prescribed to take polyethylene glycol, mosapride and other drugs to promote defecation. Patients with colorectal melanosis should seek timely medical attention and follow the doctor’s instructions to eliminate the causative factors, thus promoting the improvement of the condition, so as to avoid colorectal melanosis persists, inducing other gastrointestinal diseases and affecting the patient’s health.