[Acute verapamil poisoning. 6 cases. Review of the literature]

Abstract

Six cases of acute verapamil poisoning are reported. The dose ingested ranged between 1.2 and 9.6 g. In all cases other drugs had also been ingested and especially betablockers in two cases. Symptomatology included a cardiogenic shock in two cases and an atrioventricular block in four cases. A hemodynamic study in one case showed a cardiogenic shock with increased systemic vascular resistances. The treatment of cardiogenic shock included artificial ventilation, several vasopressors and inotropic agents and cardiac pacing in one case. All patients recovered without sequelae. A toxicokinetic study performed in two cases showed plasma half lives of 7.9 and 13.2 hours, total body clearances of 425 and 298 ml/min. Only 2 to 4.2 per cent of the dose ingested were eliminated in urine. These results confirm the severity of verapamil overdose and the efficacy of symptomatic treatment by inotropic agents. The high rate of spontaneous elimination by hepatic metabolism does not justify drug removal by extra-corporeal methods.