Purpose: We investigated the effect of the combination of the doxazosin gastrointestinal therapeutic system and 10 mg vardenafil on the hemodynamic status of patients with benign prostatic hyperplasia and erectile dysfunction.
Materials and methods: This was a double-blinded, randomized, placebo controlled crossover trial. Patients with benign prostatic hyperplasia and erectile dysfunction treated with the doxazosin gastrointestinal therapeutic system on a regular basis, with no other antihypertensive events, were recruited. Subjects took 10 mg vardenafil or placebo in a randomized crossover fashion with a washout period of at least 7 days between each treatment. The supine and standing blood pressure of the subjects was recorded from 1 hour before to 6 hours after the administration of vardenafil or placebo. The primary outcome of the study was the maximal change in standing systolic blood pressure of the subjects from 1 half hour before to 6 hours after the administration of drugs.
Results: A total of 37 patients, 25 (67.6%) and 12 (32.4%) on the doxazosin gastrointestinal therapeutic system at 4 mg and 8 mg, respectively, completed the trial. The combination drug therapy resulted in a maximal decrease in standing systolic blood pressure of 6.18 mm Hg (95% CI -12.02, -0.33; p = 0.039). Only 1 patient had an asymptomatic standing systolic blood pressure of less than 85 mm Hg. Otherwise no symptomatic hypotension or clinically significant adverse cardiovascular event was observed during the study.
Conclusions: In patients on the doxazosin gastrointestinal therapeutic system for benign prostatic hyperplasia a single 10 mg dose of vardenafil had no symptomatic hemodynamic effects.