Priapism Associated With the Rapid Titration of Prazosin: A Case Report.

Priapism is a urologic emergency that is defined as a prolonged erection in the absence of sexual stimulation. Ischemic priapism is the most common form and is characterized by low arterial blood flow and absent venous outflow. Some potential triggers of ischemic priapism include malignancy, sickle cell disease, illicit drug use, and certain medications. Prazosin, an alpha-1 adrenergic antagonist, is used for the treatment of chronic hypertension, benign prostate hyperplasia, and (post-traumatic stress disorder (PTSD) related nightmares. The alpha-adrenergic antagonistic effect of prazosin results in decreased venous blood flow, including to the smooth muscle tissue located within the corpus cavernosum. Slowly titrating prazosin allows the body to adapt to the vasodilatory effects of the medication. Without titration, a dysregulation in blood flow to the penile vasculature can result in prolonged erection. We report a case of priapism that resulted due to rapid titration of prazosin.