Endocrine Abstracts

Subjects and methods: We performed nocturnal penile tumescence and rigidity monitoring (NPTRM) in order to study the effects of Tadalafil on sleep-related erections in 23 adult healthy men (age: 34.27±8.48 years). The subjects were randomly administered Tadalafil, 10 mg tablet, the 1st (N1) or the 2nd (N2) night (Group A and B respectively) of 3 consecutive nights of erections’ monitoring. In Group A the 3rd night monitoring was regarded as control (N-ctr); in Group B the 1st night. Tadalafil was administered 2 h after last food assumption before bedtime. The NPTRM parameters analyzed were: number of valid erections, total duration of rigidity ≥60% and ≥70% maximum rigidity, maximum increase of tumescence and total duration of increase of tumescence ≥30 mm.

Results: Number of valid erections (p N-ctr vs N1: <0.01; p N-ctr vs N2: 0.01), total duration of rigidity ≥70% (p N-ctr vs N1: 0.03; p N-ctr vs N2: 0.05) and maximum increase of tumescence (p N-ctr vs N1: 0.03; p N-ctr vs N2: 0.03) were significantly higher in nights 1 and 2 after Tadalafil than in control night; no differences occurred between the 2 nights after Tadalafil. Total duration of rigidity ≥60% (p N-ctr vs N1: 0.03; p N-ctr vs N2: ns) and total duration of increase of tumescence ≥30 mm (p N-ctr vs N1: <0.01; p N-ctr vs N2: 0.06) showed higher values only in night 1 after Tadalafil than in control night. In parenthesis values are mean±S.E.M.

Conclusion: Our data suggest that Tadalafil is efficacious in improving sleep-related erections. Furthermore in normal men Tadalafil improved NPTRM also in the second night after 24 h from the drug assumption.