Hemodynamic interaction study between the alpha1-blocker alfuzosin and the phosphodiesterase-5 inhibitor tadalafil in middle-aged healthy male subjects.

Author(s): Giuliano F, Kaplan SA, Cabanis MJ, Astruc B

Affiliation(s): Neuro-Urology Unit, Department of Neurological Rehabilitation, Raymond Poincare Hospital, Garches, France. giuliano@cyber-sante.org

Publication date & source: 2006-06, Urology., 67(6):1199-204.

Publication type: Randomized Controlled Trial

OBJECTIVES: To examine the hemodynamic interactions of the phosphodiesterase type 5 (PDE-5) inhibitor tadalafil with the uroselective alpha1-blocker alfuzosin (10 mg daily), commonly prescribed for benign prostatic hyperplasia-related lower urinary tract symptoms. Erectile dysfunction is commonly associated with lower urinary tract symptoms. PDE-5 inhibitors are the first-line treatment of choice for erectile dysfunction. When co-administered with alpha1-blockers, PDE-5 inhibitors could induce orthostatic hypotension. METHODS: During each of the two periods of a randomized, double-blind, placebo-controlled, crossover study, 18 healthy middle-aged men received alfuzosin 10 mg daily for 7 days and either a single 20-mg dose of tadalafil or placebo on day 7. The blood pressure and heart rate were monitored before and for 24 hours after tadalafil or placebo. RESULTS: The combination of tadalafil 20 mg with alfuzosin 10 mg daily elicited a maximal decrease in standing systolic blood pressure that was not significantly different from that after placebo (mean difference 4.35 mm Hg, P = nonsignificant). Analysis of the blood pressure outliers showed that only 1 subject had an asymptomatic standing systolic blood pressure of less than 85 mm Hg. No vasodilatory adverse events were observed with the combined medication. CONCLUSIONS: In healthy, middle-aged men, tadalafil 20 mg showed no clinically relevant hemodynamic interactions with alfuzosin 10 mg daily.