Vasopressin for persistent hypotension due to amlodipine and olmesartan overdose: A case report

BACKGROUND: While there are consensus recommendations for managing calcium channel blocker (CCB) toxicity, reports on angiotensin II receptor blocker (ARB) toxicity and management are limited. Herein, we report a case of catecholamine-refractory hypotension due to CCB and ARB overdose. CASE PRESENTATION: A 54-year-old woman with underlying hypertension was brought to the emergency department after she attempted suicide by ingesting 345 mg of amlodipine, a CCB, and 340 mg of olmesartan, an ARB. She was hypotensive, which was considered vasodilatory because of high cardiac and low systemic vascular resistance indices. Hypotension persisted despite the administration of norepinephrine and epinephrine. Intravenous calcium gluconate, glucagon, and high-dose insulin euglycemia therapy, which were initiated because CCB toxicity was suspected, failed to raise her blood pressure. The presence of normal anion-gap metabolic acidosis and the fact that the patient remained hypotensive suggested that the hypotension might have been due to the effect of ARB. Vasopressin was finally administered, which improved her hemodynamic status. She was weaned off all vasopressors on day 3. DISCUSSION: There is no consensus recommendation for ARB toxicity. Since chronic use of ARBs at conventional doses can block the sympathetic nervous and renin-angiotensin systems, catecholamines may not effectively increase blood pressure in cases of hypotension due to ARB overdose, for which vasopressin could be indicated. CONCLUSIONS: Vasopressin could be an option for treating hypotension secondary to ARB and CCB toxicity when catecholamines and treatment for CCB toxicity fail.