Erectile dysfunction drugs altered the activities of antioxidant enzymes, oxidative stress and the protein expressions of some cytochrome P450 isozymes involved in the steroidogenesis of steroid hormones.

It is concluded that ED drugs induced the activities of both SOD and catalase which consequently decreased MDA level. Decrement in MDA levels and oxidative stress could therefore sustain the erection for a long period of time. On the other hand, it is not advised to use these drugs for a long-term since the protein expressions of CYP isozymes involved in steroidogenesis as well as the numbers of spermatocytes in testes were decreased.