chloasma /klō·az″mə/ [Gk, chloazein, to be green] , tan or brown pigmentation, particularly of the forehead, cheeks, and nose, commonly associated with pregnancy, the use of oral contraceptives, or hormone replacement therapy. The hyperpigmentation may be permanent or may disappear, only to recur with subsequent pregnancies or use of oral contraceptives, and is frequently treated with bleaching agents such as hydroquinone. Also called gravidarum chloasma, mask of pregnancy, melasma.
