A Fatal Case of Amlodipine Toxicity Following Iatrogenic Hypercalcemia

Using calcium salts in management of amlodipine overdose is challenging. A 25-year-old male with known history of adult polycystic kidney disease presented with hypotension, tachycardia, and intact neurological status after ingestion of 450 mg of amlodipine. Immediately, normal saline infusion and norepinephrine were initiated. Two grams of calcium gluconate was injected, followed by intravenous infusion of 1.16 mg/kg/h. The patient was put on insulin-glucose protocol to maintain euglycemia and hyperinsulinemia. Electrocardiography demonstrated junctional rhythm. Serum creatinine was 2.5 mg/dL with metabolic acidosis. By the end of 24 h post-admission, his consciousness, blood pressure, and urine output were normal. Almost 32 h post-admission, he became disoriented and his oxygen saturation decreased and therefore was mechanically ventilated. Second chest X-ray showed pulmonary edema. Serum calcium level increased to 26.1 mg/dL. Calcium was discontinued, and furosemide infusion and calcitonin were intravenously administrated. Urine output increased and hemodialysis improved pulmonary edema and serum calcium level with no change in consciousness. Three days after admission, the patient became anuric and developed multi-organ failure and died 5 days post-admission. To avoid the consequences of excessive infusion of calcium in renal failure patients, the minimum calcium dose with close monitoring is recommended.