EVALUATING THE EFFECTS OF AN ALPHA-2-ADRENOCEPTOR ANTAGONIST ON ERECTILE FUNCTION IN THE HUMAN MALE .2. THE ERECTILE RESPONSE TO EROTIC STIMULI IN MEN WITH ERECTILE DYSFUNCTION, IN RELATION TO AGE AND IN COMPARISON WITH NORMAL VOLUNTEERS

The effect of a new alpha-2 adrenoceptor antagonist on erectile functi on was assessed in 24 men with probable psychogenic erectile dysfuncti on. The drug was given in two dosages. together with placebo, by intra venous infusion in a balanced cross over design. Once plasma levels we re established, erectile, subjective and haemodynamic responses to ero tic fantasy and films were measured. Subjects were divided into two ag e groups, ''Younger'' (i.e. less than 45 years) and ''Older'' (greater than 45 years). There was a significant though modest increase in the duration of erectile response with the high dose of the drug, but onl y in the younger men. There were also drug effects on haemodynamic res ponses confined to the younger men, who showed markedly reduced respon ses during placebo administration when compared with the older dysfunc tional men and with young ''functional'' volunteers. The findings rais e the possibility that in younger men with psychogenic erectile failur e, there is an inhibition of general arousal responses to erotic stimu li which is partially reversed by this drug. In the older men, the dif ferent pattern of response suggests that a) there may be a decline in response to the drug with age and b) other age-related factors are pla ying an important part in the aetiology of their erectile failure.