Despite the name "melanosis," the pigment isn't melanin. The Pigment: It is actually lipofuscin, a "wear and tear" pigment. The Process: Anthraquinone laxatives cause apoptosis (cell death) of the colonic epithelial cells. Pigmented Oral Lesions: Clues to Identifying the Potentially Malignant Consultant360 Pigmented Lesions and Melanoma Plastic Surgery KeyPlastic Surgery Key How Can You Tell if It's Melanoma or Just a Mole? Oral melanotic macula on the lower labial vestibular mucosa on a Download Scientific Diagram