A Case Report on the Role of Plasma Exchange in the Management of a Massive Amlodipine Besylate Intoxication

Therapeutic plasma exchange is a procedure used to remove pathologic substances from a patient's blood that has proven useful in some cases of drug overdose. Overdose by calcium channel blocker antihypertensive agents has been shown to be a cause of significant morbidity and can often times prove fatal. These agents cause systemic hypotension by inhibiting cell membrane calcium channels, which leads to a slowing of intracardiac electric conduction with consequent impairment of myocardial function and widespread vasodilation. Shock and metabolic acidosis result from the persistent hypotension. In high doses, calcium channel blocking agents cause insulin resistance. We describe the case of a previously healthy young woman who ingested a massive dose of amlodipine and was treated by therapeutic plasma exchange after non-responsiveness to conventional therapy. The case illustrates the need for utilization of therapeutic plasma exchange in the emergency management of certain cases of severe amlodipine overdose.