Idiopathic hirsutism (IH) is defined as hirsutism in conjunction with normal ovulatory function and normal serum androgen levels. The pathogenesis of IH is still not clear. Increased peripheral 5 alpha-reductase enzyme activity and abnormalities of androgen receptor gene polynnorphisms have been postulated to explain the pathogenesis of this disorder. It is diagnosed in women who have hirsutism, normal ovulatory function, and normal levels of serum total or free testosterone. Combination treatment of IH, including androgen suppression, peripheral androgen blockade and cosmetic methods is most effective.