Chlorpromazine-Tadalafil Interaction Leading to Refractory Ischemic Priapism and Penile Prosthesis Implantation

Introduction: Priapism is a rare urological emergency characterized by a persistent, often painful penile erection unrelated to sexual stimulation. Antipsychotic medications, including chlorpromazine, are known to cause priapism through their alpha-adrenergic blocking properties. Case Presentation: We present the case of a 56-year-old male who developed refractory ischemic priapism following self-medication with oral chlorpromazine for hiccups after taking tadalafil 20 mg 24 hours prior for erectile dysfunction. This combination created a clinically significant drug interaction. The patient had experienced a brief priapism episode 10 years earlier following chlorpromazine use alone, establishing chlorpromazine as the primary causative agent. Despite systematic management with corporal aspiration, intracavernosal injection of sympathomimetics, and distal T-shunt, the patient experienced recurrent priapism necessitating penile prosthesis implantation. Discussion After thorough exclusion of alternative etiologies, this case provides compelling evidence for chlorpromazine as a causative agent of priapism, with the synergistic interaction with phosphodiesterase type 5 inhibitors exacerbating the condition to a severe, treatment-resistant state. Conclusion This report emphasizes the importance of recognizing this potentially dangerous drug interaction and provides specific clinical recommendations for prevention and management.