Erectile dysfunction can be caused by the inability for the smooth muscles in the erectile chambers to relax, allowing blood in the penis to be trapped and erections to be maintained. Injecting either Botox or Dysport, both botulinum toxins, into the corpora cavernosa of the penis may improve erectile function by approximately 20% by enhacing the ability of the muscles in that location to relax. Erections still need to be supplemented with medication or low intensity shockwave therapy as botulinum toxin alone cannot effectively treat erectile dysfunction.