lichen planus

lichen planus A common skin disease that features small, itchy pink or purple spots on the arms or legs. The abnormal areas on the skin in lichen planus are typically flat-topped (hence the term planus), itchy, and frequently have a polygonal or angular shape. Lichen planus can occur anywhere on the body but is characteristically found on the wrists, shins, lower back, and neck. Lichen planus on the scalp may lead to hair loss. The causes of lichen planus are unknown. However, it can be triggered by the use of certain drugs, such as thiazide diuretics, phenothiazines, and antimalarials. Treatment involves use of topical corticosteroids. In most cases, the disease spontaneously regresses 6 months to 2 years after onset.