In the early 1990's, researchers working for Pfizer in England were studying a drug for high blood pressure and chest pain due to heart disease. During the clinical trials, they found that this drug didn't do well in treating either of the indications for which the drug was intended. The side effects of this drug, were a pleasant surprise - for both the people taking it and for the company funding its development. The drug would later be approved by the FDA in 1996 and known as Viagra® (sildenafil).
Viagra® changed the sexual landscape for men and women. As of 1996, erectile dysfunction (ED) was no longer an untreatable consequence of old age. This little blue pill pumped new life into senior living communities around the world and reinvigorated the entire state of Florida.
Since then, however, little has changed in the way of medical treatment for ED. There are a number of off-label treatments for ED, some more effective than others. There are fewer FDA-approved medications for the treatment of erectile issues. Furthermore, many men get to a point where drugs like Viagra® no longer are effective. However, the current treatment landscape may be changing.
Botox® for the Penis
No - there are no large studies on the ability of Botox to improve the appearance of fine lines and wrinkles of the penis. The aesthetic qualities of the male genitals are of relatively little importance to most when compared to the ability to perform as expected. However, in the future, Botox may be a potential replacement for the little blue pill named above.
In 2018, researchers published a paper in Sexual Medicine Reviews, that highlighted the potential for botulinum toxin (most know it by the trade name Botox®) to be used in treating erectile dysfunction. The toxin works by preventing activation of a specific muscle by nerves. Because of the drug's mechanism, botulinum toxin was previously considered as a potential treatment for other men's health issues such as premature ejaculation.
In 2021, Andrology published the results of a double-blind randomized placebo-controlled prospective comparative study that demonstrated the safety and efficacy of botulinum toxin for the treatment of erectile dysfunction. Included in the study were men who had failed treatment with PDE5 inhibitors such as Viagra® or Cialis®. Patients were given 100 units of botulinum toxin as a single intra-cavernous injection (an injection directly into the penis). The men in the placebo group were injected with normal saline. 53% of the patients injected with botulinum toxin were able to achieve an erection with satisfactory hardness for vaginal penetration. As a comparison, a meta-analysis of clinical trials with sildenafil (the active drug in Viagra®) showed a success in only 57% of patients. A different study published in Andrology found that botulinum toxin works using as little as 50 units. However, this study found that injecting 100 units only once had effects lasting as long as 6 months or longer.
In 2022, the Journal of Sexual Medicine published a study evaluating the long-term effectiveness of botulinum toxin injections to treat erectile dysfunction when used with a PDE5 inhibitor (such as Viagra® or Cialis®) or a PGE1 injection (also known as Caverject®). The study used a specific form of botulinum toxin, abobotulinumtoxin-A (also know as Dysport®). The study used doses of 250 units and 500 units and found it to be effective in about 41% of men with ED for at least 6 months.
What's notable about the studies conducted is the side effects - or lack of them. The most common side effect was pain in the penis at the site on injection, which is of no surprise. However, there were no noted systemic effects.
Major Take-Aways on Botox® for Erectile Dysfunction
Botulinum toxin, including Botox®, Dysport®, Jeuveau®, or Xeomin® appear to be potentially a safe second-line treatment for men with erectile dysfunction. However, none of the medications are yet approved by the FDA for this indication. As a result, patients should be notified that the use of botulinum toxin is currently an off-label treatment for erectile dysfunction. Also, larger trials are likely warranted to ensure the safety profile of botulinum toxin for the treatment of erectile dysfunction is worth the risk.
Sources
Abdelrahman IFS, Raheem AA, Elkhiat Y, Aburahma AA, Abdel-Raheem T, Ghanem H. Safety and efficacy of botulinum neurotoxin in the treatment of erectile dysfunction refractory to phosphodiesterase inhibitors: Results of a randomized controlled trial. Andrology. 2022 Feb;10(2):254-261. doi: 10.1111/andr.13104. Epub 2021 Oct 7. PMID: 34618409.
El-Shaer W, Ghanem H, Diab T, Abo-Taleb A, Kandeel W. 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. PMID: 33784020.
Ghanem H, Raheem AA, AbdelRahman IFS, Johnson M, Abdel-Raheem T. Botulinum Neurotoxin and Its Potential Role in the Treatment of Erectile Dysfunction. Sex Med Rev. 2018 Jan;6(1):135-142. doi: 10.1016/j.sxmr.2017.07.008. Epub 2017 Aug 23. PMID: 28843941.
Giuliano F, Joussain C, Denys P. Long Term Effectiveness and Safety of Intracavernosal Botulinum Toxin A as an Add-on Therapy to Phosphosdiesterase Type 5 Inhibitors or Prostaglandin E1 Injections for Erectile Dysfunction. J Sex Med. 2022 Jan;19(1):83-89. doi: 10.1016/j.jsxm.2021.10.011. Epub 2021 Dec 20. PMID: 34937674.
