Intra-cavernous injection of BOTOX® (50 and 100 Units) for treatment of vasculogenic erectile dysfunction: Randomized controlled trial

Andrology. 2021 Jul;9(4):1166-1175. doi: 10.1111/andr.13010. Epub 2021 Apr 20.


Background: Erectile dysfunction (ED) is a socioeconomic problem.There are several options for its management including intra-cavernosal injection (ICI).

Objective: To compare the safety, efficacy, and durability of ICI of onabotulinum toxin-A (BTX) in different doses (50 and 100 U) against placebo (saline) in the management of vasculogenic ED non-responding to pharmacological therapy (phosphodiesterase type 5 inhibitors or/and ICI of trimix).

Materials and methods: A prospective randomized double-blind placebo-controlled trial was conducted between July 2016 and February 2019. A total of 176 patients were randomly assigned (1:1:1) to one of the treatment sequences: Botox 100 U group (BTX-100; 62 patients), Botox 50 U group (BTX-50; 59 patients), or placebo group (55 patients). All patients were followed up for 6 months.

Results: Significant improvement in all parameters, that is, SHIM score & Erection Hardness Score (EHS), Sexual Encounter Profile (SEP), Global Assessment Score (GAS), and Doppler parameters (p < 0.001) was observed in patients of BTX-100 and BTX-50 groups with maximum improvement at 3rd month of treatment. Around 40% of patients were responders and were able to engage in sexual intercourse. Patients in placebo group did not experience significant improvement (p = 0.264). It was noted that at the 2nd week and 3rd months after treatment, there was no statistically significant difference in the improvement of these parameters in BTX-100 and BTX-50 groups (p > 0.05). In the 6th month, there was a statistically significant difference between the aforementioned groups in favor of BTX-100 (p < 0.01).

Conclusions: Only one-time ICI of BTX (50 U and 100 U) is effective and safe for the treatment of refractory ED. This agent has a considerable long duration of action, particularly BTX-100U seems to be more durable.

Keywords: ICI; PDE5Is; SHIM score; botox; erectile dysfunction.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Botulinum Toxins, Type A / administration & dosage*
  • Double-Blind Method
  • Erectile Dysfunction / drug therapy*
  • Humans
  • Male
  • Middle Aged
  • Treatment Outcome


  • Botulinum Toxins, Type A
  • onabotulinum toxin A