Andropause.

Age-related decline in serum testosterone level may present as a constellation of signs and symptoms of hypogonadism known as andropause. However, low testosterone can also be indicative of an underlying pituitary disorder; therefore, careful workup should be performed to distinguish between benign and pathologic conditions in individual men. This article presents an overview of the etiology and pathophysiology of hypogonadism, and offers guidelines for the evaluation of men who should have further testing. The pros and cons of various testosterone formulations are discussed.