Intracavernous pharmacotherapy for erectile dysfunction

With the advent of phosphodiesterase type-5 inhibition as oral therapy, intracavernous injection of vasoactive agents has been relegated to second-line therapy for most patients with erectile dysfunction. However, the future of this category of agents remains bright as an ever-expanding number and combination of agents in use and under investigation will likely make intracavernous injection more appealing as greater efficacy, tolerability, and more rapid onset is attained. In this article, functional anatomy and physiology of human penile erection is reviewed, as are current clinical vasoactive agents including prostaglandin E-1, papaverine, and phentolamine. Emerging therapies discussed include guanylate cyclase activators, potassium channel openers, nitric oxide donors, vasoactive intestinal polypeptide, calcitonin gene-related peptide, selective alpha-1 receptor antagonists, and gene therapy. Ongoing research continues to define new roles for this effective and safe technique, which has withstood the test of time, restoring erectile function among patients with diverse ED etiologies and a variety of co-morbidities.