What is the recommended epinephrine dose for adult anaphylaxis and the preferred route with repetition?

• A. 0.3 mg IM or Subcutaneous, repeat every 5-10 minutes
• B. 0.3 mg IV bolus
• C. 0.15 mg IM, single dose
• D. 0.5 mg IM, repeat every 15 minutes

Answer: (A)

Epinephrine is the first-line treatment for adult anaphylaxis, chosen for its ability to rapidly counter airway swelling, vasodilation, and bronchoconstriction. The standard dose for adults is 0.3 mg of a 1:1000 solution given intramuscularly, typically into the mid-thigh, because this route delivers rapid, reliable absorption. If symptoms persist or recur, repeat 0.3 mg every 5–10 minutes as needed. The intramuscular route is preferred in the field because it provides faster and more predictable absorption than subcutaneous administration.

Intravenous epinephrine is not used as the initial treatment for a typical field case due to the higher risk of dangerous cardiovascular effects and the need for careful monitoring; it’s reserved for certain hospital settings with advanced monitoring and infusion protocols. The other options don’t fit standard adult practice: 0.15 mg is a common pediatric dose, not adult; 0.5 mg is not the standard adult starting dose, and a 15-minute repeat interval is longer than recommended.