A chronic skin disease in which itchy, scaly, red patches are covered with adherent scales. These red patches are almost circular in shape and form silvery white scales that can be removed easily. Red patches of this disease are found mainly on the elbows, forearms, fingers, knees, legs, feet and scalp. Very old cases, of 20 to 30 years' duration, are difficult to cure and in such cases, this disease spreads all over the back and abdomen.
