Vasopressor-Refractory Shock From Clozapine Overdose Treated With Synthetic Angiotensin II Infusion

BACKGROUND: Clozapine is an atypical antipsychotic with potent alpha-adrenergic blocking properties when administered at high dosages, resulting in vasodilatory shock in overdose settings. CASE SUMMARY: A 39-year-old man presented with profound catecholamine- and vasopressin-refractory vasodilatory shock following massive clozapine ingestion. Angiotensin II was initiated when the patient was requiring 2.2 µg/kg/min norepinephrine equivalents of vasopressor support, resulting in a prompt increase in the perfusion pressure. All vasopressors were liberated within 18 hours of angiotensin II initiation, and the patient was discharged with no deficits. CONCLUSIONS: Synthetic angiotensin II may represent a therapeutic option for refractory hypotension resulting from high dosages of clozapine or other potent alpha-adrenergic blocking medications.