Efficacy, Satisfaction, and Drop-out Rate of Alprostadil (Prostagladin E1) Intracavernosal Injection According to Etiologic Cause of Erectile dysfunction

Park, Jung Rae; Kim, Chun Il; Park, Choal Hee

Abstract

PURPOSE: Intracavernosal self-injection therapy is now being used widely to treat erectile dysfunction. Although several intracavernosal therapies are available, their efficacy and safety have not been studied systematically. We investigates the efficacy and safety of intracavernosal injection of alprostadil (PGE1 ) in patients with erectile dysfunction.
MATERIALS AND METHODS
From June 1996 to March 1998, 181 patients with erectile dysfunction were included in this study. Each patient was treated initially with 10micro gram of PGE1 . If the result of the injection was unsatisfactory, 20 micro gram of PGE1 was administered. The erection was evaluated clinically by manual palpation and estimated on a 5-point scale as no response, some enlargement, full enlargement, erection sufficient for intercourse, and full rigidity. In addition, each patient assessed his satisfaction with the treatment using a 3-point scale as poor, fair or good. The erectile dysfunction was classified as psychogenic, vascular, diabetic, neurogenic, or undetermined. To determine possible side effects, penile pain, hematoma, prolonged erection, priapism, and so forth were recorded by a questionnaire.
RESULTS
Of the 181 men in this study, 60 (33.2%), 45 (24.9%), 42 (23.2%), 14 (7.7%), and 20 (11.0%) were judged to have psychogenic, vascular, diabetic, neurogenic, and undetermined causes of erectile dysfunction, respectively. A good erectile response to PGE1 was seen in 59 (98.4%), 38 (84.4%), 37 (88.1%), 13 (92.9%), and 16 (80%), respectively, of the patients in these groups. Satisfaction with the treatment was reported by 59 (98.3%), 39 (86.6%), 38 (90.5%), 13 (90%) patients. Only three drug-related side effects were observed: penile pain in 54 patients (33.5%), hematoma in 5 (2.8%), and prolonged erection in 4 (2.4%). Nevertheless, the dropout rate was 46% (83/181). The causes of discontinuation within 3 months were absence of sexual partner (8.8%), recovery of erectile function (9.5%), difficulty of manipulation (19.3%), needle phobia (22.7%), pain (21.5%), and economic status (18.2%).
CONCLUSIONS
PGE1 was highly effective at producing an erection satisfactory for vaginal intercourse. The response rate was higher in psychogenic and neurogenic impotence than in vascular and diabetic impotence. Given the freedom from adverse effects such as fibrotic plaques, priapism, and liver dysfunction, PGE1 seems to be a preferable alternative to other drugs for intracavernosal injection therapy and is currently the only FDA-approved drug for this purpose. However, the dropout rate was high. Dilated attention to the procedure and careful follow-up are crucial to achieve maximal success and decrease the dropout rate.