A patient experiencing anaphylactic shock receives epinephrine but remains hypotensive. Blood pressure is: 82/50 mmHg. What is the next priority intervention?

When a patient in anaphylactic shock remains hypotensive despite epinephrine administration, the next priority intervention is initiating rapid IV crystalloid fluid infusion. Anaphylaxis causes massive vasodilation and increased capillary permeability, leading to distributive shock with intravascular volume depletion. Even after epinephrine partially restores vascular tone, the loss of fluid into the interstitial space requires aggressive volume replacement. Large-volume isotonic crystalloid — typically normal saline — is given rapidly to restore circulating volume and improve blood pressure. Applying oxygen alone does not address the hemodynamic instability and would be insufficient as the sole next step. Corticosteroids play a role in preventing biphasic anaphylaxis and reducing prolonged inflammatory responses, but they have a delayed onset of action (hours) and cannot correct acute hypotension. Antihistamines such as diphenhydramine help manage urticaria and itching but have no meaningful effect on cardiovascular collapse and are not a priority intervention for ongoing hypotension. The correct sequence in refractory anaphylactic shock is to ensure adequate vascular volume alongside continued vasopressor support, making rapid crystalloid infusion the correct next step.