Titration study of MUSE (Medicated Urethral System for Erection) in erectile dysfunction

We assessed the erectile responses and adverse reactions to prostaglandin E1 delivered via the medicated urethral system for erection (MUSE) in a titration study to determine optimal dose.

Sixty-four patients with erectile dysfunction underwent in-office testing with MUSE to determine erectile response. Following thorough instructions, patients were taught how to use MUSE themselves. The titration study started with a dose of 125 micrograms, and increased to 250 micrograms, 500 micrograms, and finally 1,000 micrograms. In patients who had an erectile response, erection scoring, color duplex Doppler study, blood pressure monitoring, recording of subjective complaints, and repeated laboratory examinations were performed to evaluate the positive and adverse effects of MUSE.

Forty-three of the 64 patients achieved a maximal erection with MUSE, as shown by systolic peak flow velocities in the deep penile arteries of greater than 27 cm/s on Doppler ultrasonography. One patient was unsatisfied with his erectile response and dropped out of the study. Of the 42 patients who completed the study, most (35) were satisfied with the response achieved at the higher doses of 500 micrograms and 1,000 micrograms. A modified soft rubber band was needed to achieve a satisfactory erectile response in 18 patients. Only four patients experienced serious urethral burning during MUSE application.

MUSE was effective and safe in most patients with erectile dysfunction in this study. For patients not satisfied with the extent of penile rigidity achieved with MUSE, the use of a modified soft rubber band for erectile assistance, as well as a program for improved patient education, may help to achieve a better erectile response and facilitate compliance with treatment regimens at home.