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Updated: Aug 6, 2026

Transurethral Instillation Procedure in Adult Male Mouse
Published on: November 2, 2017
Treatment of men with erectile dysfunction with transurethral alprostadil. Medicated Urethral System for Erection
H Padma-Nathan1, W J Hellstrom, F E Kaiser
1Department of Urology, University of Southern California, Los Angeles, USA.
Background:
Erectile dysfunction in men is common. We evaluated a system by which alprostadil (prostaglandin E1) is delivered transurethrally to treat this disorder.
Methods:
Alprostadil was delivered transurethrally in a double-blind, placebo-controlled study of 1511 men, 27 to 88 years of age, who had chronic erectile dysfunction from various organic causes. The men were first tested in the clinic with up to four doses of the drug (125, 250, 500, and 1000 microg); those who had sufficient responses were randomly assigned to treatment with either the effective dose of alprostadil or placebo for three months at home.
Results:
During in-clinic testing, 996 men (65.9 percent) had erections sufficient for intercourse. Of these men, 961 reported the results of at least one home treatment; 299 of the 461 treated with alprostadil (64.9 percent) had intercourse successfully at least once, as compared with 93 of the 500 who received placebo (18.6 percent, P<0.001). On average, 7 of 10 alprostadil administrations were followed by intercourse in men responsive to treatment. The efficacy of alprostadil was similar regardless of age or the cause of erectile dysfunction, including vascular disease, diabetes, surgery, and trauma (P<0.001 for all comparisons with placebo). The most common side effect was mild penile pain, which occurred after 10.8 percent of alprostadil treatments, but the pain rarely resulted in refusal to continue in the study. Hypotension occurred in the clinic in 3.3 percent of men receiving alprostadil. Hypotension-related symptoms were uncommon at home. No men had priapism or penile fibrosis.
Conclusions:
In men with erectile dysfunction, transurethral alprostadil therapy resulted in erections in the clinic and in intercourse at home.
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