Evaluation of the effect of sildenafil and tadalafil on testosterone blood level

Abstract

BackgroundErectile dysfunction (ED) is the persistent inability to achieve and/or to maintain an erection for satisfactory sexual relations. In the corpus cavernosum, phosphodiesterase type 5 inhibitor (PDE5I) increase cyclic GMP concentration and cause smooth muscle relaxation of arteries and sinusoids, thus facilitating blood flow. As a consequence, PDE5I, such as sildenafil, tadalafil and vardenafil have proved to be effective, well-tolerated drugs in the treatment of ED. Increasing the frequency of sexual intercourse increases the circulating testosterone levels, and hence PDE5I therapy may affect testicular function of ED patients. ObjectiveThe aim of this study was to evaluate and compare the effect of sildenafil and tadalafil on testosterone blood level. Patients and methodsFifty-six married male patients with ED and age range 40–70 years with low–normal total testosterone level were included. Patients were randomly allocated into two groups: group I included 28 patients with ED who received 25 mg sildenafil once daily oral dose for 2 months, and group II included 28 patients with ED who received 5 mg tadalafil once daily oral dose for 2 months. Serum testosterone and luteinizing hormone (LH) levels were evaluated before starting the treatment and after 2 months of treatment. ResultsThere was increased total testosterone level, a significant decrease in LH and increased post-treatment International Index of Erectile Function values in both groups. There was a significant increase in values of post-treatment total testosterone level and International Index of Erectile Function and a significant decrease in post-treatment LH in group II compared with group I. ConclusionDaily use of sildenafil and tadalafil increased testosterone blood level but the effect was greater with tadalafil than with sildenafil.