Vasopressor Requirements in Antipsychotic Overdose: A Poison Center Observational Study

Area of Science:

• Toxicology
• Pharmacology
• Emergency Medicine

Background:

• Antipsychotic medications can cause peripheral alpha-adrenergic antagonism, leading to vasodilation and potential hypotension.
• Hemodynamic instability may necessitate treatment with intravenous fluids and vasopressors.

Purpose of the Study:

• To determine the incidence of hypotension in patients with acute antipsychotic overdose.
• To characterize the utilization of vasopressor agents in managing antipsychotic-induced hypotension.

Main Methods:

• Retrospective cohort study analyzing electronic health records from two regional poison control centers (2004-2020).
• Inclusion criteria: single acute antipsychotic exposure, age >15, healthcare facility evaluation.
• Hypotension defined as systolic blood pressure <90 mm Hg and/or mean arterial pressure <65 mm Hg.

Main Results:

• 2070 cases of moderate to severe outcomes from single antipsychotic overdoses were analyzed.
• Hypotension occurred in 169 cases (3.8%), predominantly associated with atypical antipsychotics, especially quetiapine.
• Vasopressor therapy was administered in 9.9% of hypotensive cases, with norepinephrine being the most common agent.

Conclusions:

• Hypotension is an infrequent complication of acute antipsychotic overdose presenting to healthcare facilities.
• Vasopressor administration for antipsychotic-induced hypotension is rare.