Safety and Efficacy of Intracavernosal Injections of AbobotulinumtoxinA (Dysport®) as Add on Therapy to Phosphosdiesterase Type 5 Inhibitors or Prostaglandin E1 for Erectile Dysfunction-Case Studies

Toxins (Basel). 2019 May 21;11(5):283. doi: 10.3390/toxins11050283.


Erectile dysfunction (ED) is a highly prevalent condition with a variety of possible risk factors and/or etiologies. Despite significant advances regarding ED pharmacological management, there are still insufficient responders to existing pharmacological treatments e.g., approximately 30% of patients are insufficient responders to phosphodiesterase type 5 inhibitors (PDE5-Is). It has been recently proposed that botulinum toxin A intracavernosally (IC) delivered could be effective in these patients. Data from a retrospective uncontrolled single center study of 47 ED patients, consecutively recruited, insufficient responders to existing pharmacological treatments e.g., PDE5-Is or IC PGE1 injections treated with IC abobotulinumtoxinA 250 or 500 U as free combination with their existing treatment have been analyzed. Response rate, according to the International Index of Erectile Function-Erectile Function domain score, 6 weeks following IC abobotulinumtoxinA in combination with prior pharmacological treatment, was 54%. Two patients have reported mild penile pain on injection or during the 3 days following injection. Therapeutic efficacy did not seem to be influenced by the etiologies and/or risk factors for ED. Conversely, the less severe ED, the higher the response rate. Preliminary evidence for the therapeutical potential with acceptable safety of IC abobotulinumtoxinA as add-on therapy for ED not sufficiently responsive to standard therapy should be confirmed in randomized clinical trials.

Keywords: botulinum toxin A; combination therapy; mechanism of action; non-responders; pathophysiology; penile erection; pharmacology; sympathetic overactivity.

MeSH terms

  • Adult
  • Aged, 80 and over
  • Alprostadil / administration & dosage*
  • Botulinum Toxins, Type A / administration & dosage*
  • Botulinum Toxins, Type A / adverse effects
  • Drug Therapy, Combination
  • Erectile Dysfunction / drug therapy*
  • Humans
  • Injections
  • Male
  • Middle Aged
  • Phosphodiesterase 5 Inhibitors / administration & dosage*
  • Phosphodiesterase 5 Inhibitors / adverse effects
  • Retrospective Studies
  • Treatment Outcome


  • Phosphodiesterase 5 Inhibitors
  • Botulinum Toxins, Type A
  • abobotulinumtoxinA
  • Alprostadil