First Priority
Intramuscular epinephrine is the first-line treatment and should not be delayed for other interventions. Remove the allergen if possible, position the patient, and manage the airway aggressively. Early recognition of swelling, stridor, wheezing, and hypotension is critical.
Adjunct Medications
Diphenhydramine blocks H1 receptors and eases itching and hives but does not treat airway swelling or shock. Albuterol helps with wheezing, and corticosteroids may reduce delayed reactions. IV fluids support blood pressure in distributive shock.
Biphasic Reactions
Symptoms can return hours after the initial reaction even without re-exposure. For this reason, all patients who receive epinephrine should be transported for observation. Document the time of exposure, symptoms, and each treatment delivered.