ABSTRACT
Androgenetic alopecia (AGA), also known as common baldness or male-pattern hair loss, is the most common cause of hair loss in men. In its most classic form, it follows a distinctive pattern of hair loss, starting from bitemporal recession and going on to diffuse frontal and vertex loss, with preservation of occipital hair. A variant also exists which presents as a general diffuse hair loss, more commonly found among Asians. The pathogenesis involves androgen-induced miniaturization of terminal hairs into vellus hairs in affected regions of the scalp. Some degree of follicular miniaturization and consequential hair loss is universal and is considered to be a physiological secondary sexual characteristic. AGA is generally regarded as an aging process and only becomes a medical problem when the hair loss is excessive, premature, and distressing to the patient.
