What is the standard adult dose of epinephrine for suspected anaphylaxis in EMS?

• A. 0.15 mg of 1:10,000 solution IM
• B. 0.3 mg of 1:1000 solution IM; may be repeated per protocol
• C. 1.0 mg of 1:1000 solution IM
• D. 0.3 mg of 1:10,000 solution IM

Answer: (B)

Epinephrine is the first-line treatment for suspected anaphylaxis because it rapidly counters life-threatening symptoms by constricting blood vessels, reducing airway swelling, and opening airways through beta-adrenergic effects. For adults, the standard EMS dose is 0.3 mg of a 1:1000 (1 mg/mL) epinephrine solution given intramuscularly, typically into the mid-outer thigh, with the dose possibly repeated according to protocol if symptoms persist. The 1:1000 concentration is appropriate for IM administration and delivers the correct amount in a small volume.

Other options use concentrations or total amounts that aren’t appropriate for IM use in adults. For example, a 1:10,000 solution is used mainly for IV resuscitation, not standard IM treatment for anaphylaxis, and a 1.0 mg IM dose would be larger than commonly recommended and could raise the risk of adverse effects.