[Poisoning by delayed-release verapamil in an uremic patient]

The appearance of toxic effects upon consumption of delayed release verapamil at therapeutic doses (120 mg/12 h) in a 64 year old patient with renal failure is described. The patient presented hypotension, bradycardia due to auriculoventricular block, hepatotoxicity, slight hyperglycemia, hyperpotassemia and metabolic acidosis with increased anionic gap. The picture remitted spontaneously with support treatment following discontinuation of the medication. The pathogenesis of the syndrome and the possibility that the hepatotoxicity was the triggering factor are discussed. Extreme precaution is recommended when this type of drugs is used in severe uremic or diabetic patients.