Sexually potent and sluggish/impotent male rats were orally treated with an extract of Ferula hermonis (30 and 60 mg/kg). The acute administration stimulated sexual motivation in potent rats and improved copulatory performance in sluggish/impotent rats. This last effect was elicited only by the higher dose, which, in parallel, increased serum testosterone levels in rats. On the contrary, when the extract was subchronically administered (10 days) a marked reduction in the percentage of rats achieving ejaculation was detected, together with a general impairment of the copulatory pattern. Furthermore, the repeated administration of the extract (6 mg/kg/day for 10 days) resulted in a significant reduction of testosterone levels in comparison with controls. The present results discourage a repeated assumption of F. hermonis, while suggesting its acute administration to improve the performance in sexual dysfunctions.