Introduction and objectives: Sildnenafil citrate is a powerful phosphodiesterase type 5 isoenzyme; it is the first oral treatment to have had a significant success in treatment of erectile dysfunction (ED). After oral dosing on an empty stomach the pharmacological activity starts within 30 to 120 minutes (average 60 minutes) whereas the effect of this medication after a meal could be notably delayed. We evaluated the start of pharmacological activity in 30 patients affected by non-psychogenic ED after sublingual administration of Sildenafil citrate.
Methods: Patients participating in our study were all affected by ED whose etiology was assessed as vasculogenetic or diabetic. The study lasted 6 months. For the first 3 months patients were asked to take Sildenafil (50-100 mg) for oral administration, under normal everyday conditions, 30 minutes before planned sexual relations. During the second 3 months the patients were asked to take Sildenafil for sublingual administration (crushing the pill in the mouth and dissolving the drug under the tongue) 15 minutes before planned sexual relations. The patients did not know the purpose of the study.
Results: An appreciable reduction in the start of pharmacological activity was reported during the time of sublingual administration. In fact, while throughout the first 3 months the average pharmacological onset was 62.8 minutes (DS +/- 16.8), during the second 3 months it was 29.3 minutes (DS +/- 8.1), the mean difference in the start of pharmacological activity was 35.3 (DS +/- 12.4). The results of T-student test for paired observation were T (29) = 15.629; p-value 0.00001. During the two modalities of administration no differences were noted in the efficacy or in the frequency of adverse events. All the patients declared they preferred the sublingual way because of faster onset.
Conclusions: Even though ours is a limited study, our clinical data points out that the sublingual administration of Sildenafil is useful because of the rapid onset unrelated to meals. All the patients were reported to appreciate this method of administration, particularly in the case of unplanned sexual relations.