How would you recognize anaphylaxis, and what is the immediate field management if an epinephrine auto-injector is available?

• A. Rapid onset throat/tongue swelling, hives, wheeze, hypotension; administer epinephrine 0.3 mg IM (adult) or 0.15 mg (child) if available; call EMS; lay patient flat or with legs elevated as advised; monitor and evacuate.
• B. Gradual onset rash only; treat with antihistamines.
• C. Chest pain; give aspirin.
• D. Nausea only; rest.

Answer: (A)

Anaphylaxis is a rapid, life-threatening allergic reaction that involves multiple body systems. The strongest warning signs are sudden throat or tongue swelling, widespread hives, wheezing or breathing difficulty, and a drop in blood pressure. These features together indicate that the airway and circulation are at risk, so the first, most important action is to give epinephrine promptly because it reduces airway swelling, improves airway tone, and supports blood pressure.

If an epinephrine auto-injector is available, use it right away: inject the labeled dose into the outer thigh as an IM injection (0.3 mg for an adult or 0.15 mg for a child, per the devices you have). After administering, call EMS and arrange for urgent transport. Have the patient lie flat or with legs elevated as advised to support circulation, and monitor breathing and consciousness while evacuation proceeds. If symptoms recur or do not fully resolve, repeat the dose if you are trained and advised to do so, with EMS guidance.

Other possibilities like a gradual rash treated with antihistamines alone, chest pain managed with aspirin, or nausea with rest do not reflect the urgency of airway and circulatory compromise in anaphylaxis and do not substitute for epinephrine when this reaction is suspected.