Recurrent Priapism after Initiation of Oral Minoxidil

Introduction: We present the case of a patient with end stage renal disease on dialysis and sickle cell trait presenting with multiple recurrent priapism episodes over four weeks which were associated with the initiation of minoxidil for hypertension. Priapism is considered a urological emergency which requires prompt medical attention to prevent adverse sequelae such as erectile dysfunction. While priapism has been associated with sickle cell trait and hemodialysis likely in the setting of occlusive events, minoxidil is not readily identified as a potential trigger in patients predisposed to this condition. Case Description: This is a 46 year old male with a past medical history of end stage renal disease on thrice weekly hemodialysis for four years, hypertension, type 2 diabetes mellitus, and sickle cell trait. The patient presented to the emergency department with a painful erection which had lasted for 5-6 hours after hemodialysis. He had one prior episode approximately 3 years ago. He underwent cavernosal aspiration and injection of phenylephrine with resolution of the episode and the patient was discharged. Over the next four weeks, the patient presented twice more with similar episodes despite having started finasteride to prevent recurrence, and was treated similarly. Upon further questioning, the patient had been started on oral minoxidil 5mg daily for uncontrolled hypertension, two weeks prior to the first event. Once minoxidil was stopped, no further episodes of priapism have occurred in the following two months. Discussion: Priapism is a urological emergency and requires prompt diagnosis and treatment. Here we present a case in which recurrent episodes of priapism appeared to be temporally associated with the initiation of minoxidil and resolved following its discontinuation. While topical minoxidil has been proposed as a treatment for erectile dysfunction, we are unaware of any previous reports of an association with priapism. Minoxidil and potentially other vasodilatory agents should be considered as a potential cause of priapism, particularly in patients with other predisposing factors.