Combination of pregabalin and Amitriptyline in management of chronic idiopathic pain following penile prosthesis implantation: a pilot study

Chronic post-penile prosthesis pain is de novo pain persisting > 2 months post-operatively. This pain is inadequately reported, poorly understood and undermanaged. The purpose of this current pilot study was to improvise a medical approach to alleviate the condition and assess the combination of Pregabalin and Amitriptyline in its management. The study enrolled 9 patients complaining of idiopathic penile, pelvic, or scrotal pain persisting > 2 months after penile prosthesis implantation. Patients were prescribed pregabalin 75mg/12h (escalated after 1 week to 150mg/12h upon demand) and Amitriptyline 25mg once daily for 3 months. The pain was reassessed after 10, 30 and 100 days. The dose of pregabalin required and the side effects of the medication were noted. Findings revealed a significant decrease in pain duration (p = 0.007), frequency (p < 0.001), and intensity (p < 0.001); in glanular (p = 0.008), shaft pain (p = 0.046) but not scrotal (p = 0.112). Moreover, a significant decrease was found in sharp pain (p = 0.003) and pain aggravated by touch (p = 0.008) but not aching pain (p = 0.277). Additionally, significant improvement was reported in QoL (p < 0.001) and dose escalation of pregabalin to 150mg/12h was required in only 1 case (11%). The combination of pregabalin and amitriptyline is very effective in the management of chronic idiopathic pain following penile prosthesis implantation. However, due to the ambiguity and lack of reporting of the condition, we recommend a multicentric contribution to acknowledge the condition, and weigh its prevalence accurately, whilst evaluating the efficacy of our approach. This study received ethical approval from Ain Shams University Research Ethics Committee (REC) FWA 000017585, on 04/13/2023 (REC-FMASU@med.asu.edu.eg). no FMASU R98/2023.