Abstract

A 54 year gentleman was admitted to hospital within four hours of taking an overdose of modified release felodipine tablets, with a total dose of approximately 250 mg. The initial management comprised fluid resuscitation, calcium chloride and glucagon. He remained hypotensive and was commenced on hyperinsulinaemia-euglycaemic therapy. Hypotension persisted with the development of progressive metabolic acidosis despite increasing inotropic support, haemofiltration and high dose insulin-dextrose infusions. The patient died 60 hours post overdose. The case highlights the profound, refractory circulatory collapse and lethal consequences of significant calcium channel blocker overdose and also reviews potential management strategies to attempt to reverse these changes. Despite the lack of evidence of whole bowel irrigation in overdose per se, its role in the removal of modified release compounds has not been studied. We would strongly urge emergency departments to consider this therapeutic modality, especially in overdoses involving delayed release preparations of calcium channel blockers, which are extremely toxic in overdose and are associated with very high mortality.
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