To investigate the efficacy and safety of three different dilutions of verapamil used in intraplaque injections in an attempt to reduce Peyronie’s disease symptoms.

A total of 77 patients (age 48 ± 9 years) with chronic Peyronie’s disease were randomized into three groups, each receiving 12 intraplaque injections (1 injection every 2 weeks) of 10 mg verapamil in different dilutions. Group 1 (27 patients) received verapamil 10 mg/4 mL, group 2 (24 patients) received verapamil 10 mg/10 mL, and group 3 (26 patients) received verapamil 10 mg/20 mL. The variables, assessed before and 8 months after therapy, were erectile function (assessed by semistructured interview), plaque size, peak systolic velocity, end-diastolic velocity, left and right cavernosal arteries (assessed with dynamic Duplex ultrasonography), pain (assessed with a pain scale), penile curvature (measured using a photograph of a pharmacologically induced full erection), and side effects. Analysis of variance and the chi-square test were used to analyze the differences among the groups.

No significant differences were found in the baseline values among the groups. The peak systolic velocity of the left and right cavernosal arteries was never significantly modified. The plaque area, penile curvature, erectile function, end-diastolic velocity of the left and right cavernosal arteries, and pain improved more significantly in group 3 than in groups 1 and 2. The side effects were ecchymosis, with no significant differences among the groups.

The dilution of verapamil significantly improved its efficacy in improving Peyronie’s disease symptoms.