Bromocriptine treatment of males with pituitary tumours, hyperprolactinaemia, and hypogonadism.

Plasma prolactin concentrations were measured in thirty-four males with pituitary tumours and twenty-two patients (65%) were found to have hyperprolactinaemia. Plasma testosterone concentrations were subnormal in twenty-nine patients. Ten patients with hyperprolactinaemia were treated with bromocriptine; prolactin was restored to normal values in eight patients but testosterone secretion remained deficient. Two patients were resistant to bromocriptine. Some improvement in libido and potency was obtained after restoration of normal prolactin concentrations in four cases in spite of persistently low testosterone secretion. For maximal improvement in sexual function treatment with both bromocriptine and testosterone was required.