Epinephrine is indicated for patients with an allergic reaction when:

• A. Only when there is urticaria
• B. Wheezing and hypotension are present
• C. Only when there is a mild rash
• D. Itching without airway symptoms

Answer: (B)

The important idea is that epinephrine is used when the allergic reaction involves the airway and the circulation. In an anaphylactic reaction, wheezing signals bronchospasm and airway narrowing, while hypotension shows significant vasodilation and circulatory collapse. Epinephrine works on both fronts: it tightens blood vessels to raise blood pressure and reduce swelling, and it relaxes the airways to improve breathing. When both wheezing and low blood pressure are present, this combination indicates a serious, life-threatening reaction that needs prompt epinephrine.

Isolated symptoms like a mild rash or itching without airway involvement don’t by themselves warrant epinephrine, because they don’t show the dangerous airway or circulatory problems you’re trying to reverse. Urticaria alone can occur with milder allergic reactions, but without airway or perfusion compromise, epinephrine isn’t indicated.