Investigational noncardiovascular uses of phosphodiesterase-5 inhibitors

INTRODUCTION: At the present time, inhibitors of phosphodiesterase type 5 (PDE5) have Food and Drug Administration approval only for the treatment of erectile dysfunction and pulmonary artery hypertension, for which their mechanism of action is vasodilation and augmentation of blood flow by impeding PDE5-mediated breakdown of cyclic guanosine monophosphate. However, these agents are also being investigated in a wide range of other potential medical and surgical applications for which current treatment options are limited and in which their mechanism of action may be the same as or different from their effects in the two approved indications. Even if only some of these potential applications prove useful, the effect on clinical practice could be far reaching. AREAS COVERED: This literature review summarizes potential noncardiovascular uses of PDE5 inhibitors, with emphasis on clinical research. Topics include a variety of male genitourinary disorders other than erectile dysfunction: cutaneous ulcerations, tissue protection, neurological conditions, diabetes, cancer, transplant and reconstructive surgery, female sexual dysfunction and disorders of pregnancy. EXPERT OPINION: The exceptionally wide range of research taking place with PDE5 inhibitors holds promise not only for improved therapeutic options but also for an improved understanding of the basic biological mechanisms that underlie scientific medicine.