A few minutes after you have given an intradermal injection of an allergen during skin testing, the patient reports feeling anxious, short of breath, and dizzy. Which action included in the emergency protocol should you take first?

• A. Start oxygen at 4 L/min using a nasal cannula.
• B. Obtain IV access with a large-bore IV catheter.
• C. Give epinephrine (Adrenalin) 0.3 mL intramuscularly.
• D. Administer 3 mL of nebulized albuterol (Proventil) 0.083%.

Answer: (C)

The primary issue here is a life-threatening allergic reaction that can rapidly progress to airway compromise and shock. The first action in this emergency protocol is to administer epinephrine intramuscularly. Epinephrine rapidly counteracts the main problems of anaphylaxis: it causes vasoconstriction to raise blood pressure and reduce edema, stabilizes capillary membranes, and bronchodilates to improve airway airflow. This single intervention addresses the underlying pathophysiology and can prevent progression to more severe failure.

Oxygen is important for any hypoxemia, and establishing IV access is crucial for fluids and additional meds, but neither reverses the reaction as quickly or effectively as epinephrine. Nebulized albuterol can help with bronchospasm, but it does not stop the vascular permeability and airway edema driving anaphylaxis, so it should follow epinephrine, not precede it. In adults, the usual IM dose is 0.3 mL of 1:1000 epinephrine, given in the mid-thigh, with repeat dosing if symptoms persist. After epinephrine is given, continue monitoring, support the airway, give oxygen as needed, and prepare for further treatment per protocol.