EVALUATING THE EFFECTS OF AN ALPHA-2-ADRENOCEPTOR ANTAGONIST ON ERECTILE FUNCTION IN THE HUMAN MALE .1. THE ERECTILE RESPONSE TO EROTIC STIMULI IN VOLUNTEERS

The effects of a new alpha-2 adrenoceptor antagonist on erectile funct ion was assessed in 12 normal volunteers (mean age 28.7, range 20-42), using a double blind, placebo controlled design with two doses of dru g and three testing sessions. The drug was administered by intravenous infusion and erectile responses to erotic fantasy and films were moni tored by a Rigiscan device. Four effects of the drug were observed; (i ) an increase in spontaneous erections; (ii) increased subjective rati ngs of sexual arousal, before presentation of erotic stimuli; (iii) in creased duration of erectile response to erotic stimuli; and (iv) incr eases in systolic BP and HR both before and during erotic stimulation. These effects were largely restricted to the high dose of the drug. A dverse effects of the drug were minimal.