Effect of bulbospongiosus muscle injection with botulinum-A toxin for treatment of lifelong premature ejaculation; a randomized controlled trial

Abstract This study aimed at assessing a new line of treatment for lifelong premature ejaculation which is botulinum-A toxin injection into the bulbospongiosus muscle. Sixty patients with lifelong premature ejaculation were independently randomized into 2 groups; group I, 100 U botulinum-A toxin at 10 U/ml saline was injected with ultrasound guidance into the bulbospongiosus muscle and group II which was injected with similar volume of saline. The primary outcome was to compare both groups for changes in the Premature Ejaculation Profile (PEP), Intravaginal Ejaculatory Latency Time (IELT) and partner’s satisfaction at 1, 3 and 6 months after intervention. The second outcome was to compare the adverse events in both groups. Fifty-seven patients completed the study. In group I, the mean PEP increased significantly at 1- ( P = 0.02) and 3- months ( P = 0.04) with insignificant increase at 6-month ( P = 0.6) of follow-up. Also, no significant changes had been noted in IELT or partner’s satisfaction scores throughout the study duration ( P > 0.05). In group II, no significant changes had been noted in the PEP, IELT and partner’s satisfaction scores throughout the study duration ( P > 0.05). There were insignificant differences in the changes in the mean PEP ( P = 0.7, 0.6 and 0.4), IELT ( P = 0.6,0.6 and 0.5) and partner’s satisfaction scores ( P = 0.5,0.7 and 0.3) in comparison to the baseline values at 1-, 3- and 6- months, respectively between both groups. Adverse events were observed in only 3 patients (5.3%). In group I, mild erectile dysfunction and post micturition dribbling were reported in one patient each. Where in group II, one patient reported bleeding per urethra ( P = 0.5). To conclude, injection of botulinum-A toxin into bulbospongiosus seems to be safe but failed to prove clinical efficacy for treatment of lifelong premature ejaculation when compared to placebo.