Introduction
Priapism is an erection persisting for over four hours, often associated with pain. Most commonly, priapism is coupled with the absence or reduction in intracavernosal arterial flow, known as ischemic priapism, which implicates emergent intervention to prevent fibrosis of corpora cavernosa and the subsequent risk of long-term erectile dysfunction. Priapism incidence ranges from 0.3 to 1.5 per 100,000 men, with approximately 30% drug-induced. Pharmacological interventions for erectile dysfunction, including intracavernosal injection of erectogenic agents (e.g., papaverine and alprostadil) as well as oral intake of phosphodiesterase-5 inhibitors (PDE5i), are known causes of priapism. While intracavernosal therapy’s role in priapism is well-evidenced, priapism from PDE5i is only recorded by limited case reports. Recently, a study demonstrated that priapism accounts for 0.7% of reported adverse drug reactions (ADR) for PDE5is, suggesting that extensive patient counseling regarding priapism when prescribing may be unnecessary.
We aim to verify the low incidence of priapism among PDE5i users in a large international dataset. Further, we aim to assess the differences between different PDE5i products and common intracavernosal agents in the development of priapism. We identify age groups at risk to help practitioners better counsel their patients.