Two separate mechanisms account for the increased pigmentation and each may arise in the epidermis, dermis, or mixed (dermis and epidermis). Typically, patients endure the same consequences.

The skin contains three layers: The epidermis, dermis and a layer of fatty tissue. Structures within these layers are involved in thermoregulation. Sweat glands in the dermis release more sweat ...

Melasma is a common acquired pigmentary disorder characterized by a slowly progressive, symmetrical hypermelanosis with an irregular coloration, ranging from light brown to gray and dark brown.