To the ER? Can Patients Treat Their Anaphylaxis at Home?

PURPOSE OF REVIEW: To discuss if all patients who use self-injectable epinephrine outside the hospital setting require immediate emergency care.

RECENT FINDINGS: Prior to 2023, anaphylaxis management guidance universally recommended that patients who use self-injectable epinephrine outside of the hospital or clinic setting immediately activate emergency medical services and seek further care. Additional food-induced anaphylaxis management recommendations specified that all patients always carry 2 auto-injector devices and give a second dose of epinephrine if there was not immediate response within 5 min of injection. Patients presenting for emergency care after epinephrine are often observed for up to 4-6 h afterwards, even when completely asymptomatic. These management steps have lacked evidence for improving outcomes, and universal implementation of these approaches is not cost-effective as guidance for food allergic patients. Epinephrine pharmacokinetics and pharmacodynamics suggest that peak physiologic response is more likely to occur closer to 15 min than before 5 min, that few patients require a second dose of epinephrine as most stabilize within 15 min of use, that 60 min of observation after a patient stabilizes after epinephrine use may be adequate as patients infrequently have further sequelae, and that not everyone needs to carry 2 epinephrine auto-injectors on their person at all times. The most recent anaphylaxis practice parameter promotes a contextualized approach to these management questions, outlining the option for watchful waiting to gauge response to epinephrine before seeking emergency care, which has been proven as a more cost-effective management strategy. The recent updated anaphylaxis care guidelines support the evolution of anaphylaxis care, in that universal, immediate activation of emergency services is not required for using self-injectable epinephrine outside the hospital setting.