Chronic amantadine treatment enhances the sexual behaviour of male rats

The acute administration of amantadine (AMA), a dopaminomimetic and NMDA glutamatergic receptor antagonist also used as an anti-Parkinsonian agent, stimulates male rat sexual behaviour. However it remains unclear whether long term AMA supplementation might also provoke a similar increase in male rat sexual conduct. In the present study, male rats were administered AMA (5-50 mg/kg/day) or vehicle daily for 21 days and their sexual response was monitored weekly. Chronic treatment with AMA effectively increased the sexual response of male rats, similarly to what had been observed before with acute amantadine treatment. The main effect of chronic AMA treatment occurs in arousal and in ejaculatory response, whilst the excitatory component was not affected. The 21-day treatment with AMA did not lead to tolerance, suggesting that perhaps AMA could be used in male human patients to prevent sexual inhibition caused by anti-depressant and anti-psychotic agents.