Propionyl l carnitine Stock Photos & Footage Commercial Stock Media Science Source Images This patient has multiple labial melanotic macules. These are essentially freckles of the lips. These most commonly involve the lower lip. This patient had involvement of both the upper and lower lips. Rexdrive Amino with L Arginine HCl, L Citrulline, Acetyl L Carnitine Arginate DiHydrochloride, and Glycine 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 L Carnitine Explained: What This Amino Acid Does for Your Body