Histological alterations in the testicular tissue induced by sildenafil overdoses.

Twenty adult male rabbits (Oryctolagus cuniculus) received sildenafil (0, 1, 3, 6, 9 mg/kg/day) for 4 weeks to investigate the testicular histological alterations induced by overdoses of this drug. Exposure to overdoses of sildenafil had provoked tubular and interstitial histological alterations. Abnormality in the germinal epithelium of the seminiferous tubules included spermatocytes karyopyknosis, spermatocytes degeneration, desquamation, spermatid giant cells and arrest of spermatogenesis. Additionally, increased Leydig cells cellularity, tubular degeneration, thickening of the interstitium were also observed. The encountered histological findings indicate that chronic exposure to sildenafil overdoses produces significant morphological and histological alterations in the testes which finally might lead to complete arrest of spermatogenesis.

Sildenafil citrate ingestion and prolonged priapism and tachycardia in a pediatric patient.

INTRODUCTION: Little is known about the toxicity of sildenafil overdose in the pediatric population. We present a case of prolonged priapism and tachycardia due to unintentional sildenafil overdose in a child. CASE REPORT: A 19-month-old male ingested up to six 50 mg Viagra tablets 45 minutes prior to presentation at the emergency department. Initial vital signs included temperature 98.2 degrees F, blood pressure 90/58 mmHg, heart rate 140, respirations 20, and oxygen saturation of 100% on room air. The child weighed 10.4 kg. Physical exam revealed a happy, smiling, laughing toddler who was cooperative with all aspects of his exam. He had mild facial flushing and an erect penis which was normal in color and had a capillary refill of two seconds. Precordial palpation did not show evidence of increase dynamic force, his heart sounds were regular, and no ectopy was noted. His peripheral pulses were strong and regular in all four extremities. No gastrointestinal decontamination was performed. The patient was started on maintenance IV fluids and admitted to the pediatric floor for observation. The patient had a non-painful tumescent penis and mild tachycardia for about 24 hours post-ingestion. The child never had pain from the constant erection. Sildenafil concentration drawn approximately seven hours after ingestion was 3900 ng/ml (reporting limit 24 ng/ml) and N-desmethylsildenafil level was 1700 ng/ml (reporting limit 24 ng/ml). CONCLUSION: This case of pediatric sildenafil ingestion (up to 30 mg/kg) initially resulted in facial flushing and priapism. The child had asymptomatic tachycardia and prolonged priapism that persisted until hospital discharge approximately 24 hours after ingestion. The erection was non-painful and required no urologic intervention, most likely representing a high flow state. In this ingestion, only supportive care was required.