Pronunciation of Melanotic Definition of Melanotic 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. Melanotic macule. Benign. Dark spot on labia (or lip). Analogous to lentigo simplex. Hyperpigmented basal keratinocytes & dermal melanophages. Slight in single basal melanocytes; NO nests. More info like this in Melanoma Pictures: Skin Changes and What to Look For Benign mole (melanocytic naevi) MySkinDoctor