Which medication is administered for anaphylaxis if indicated?

• A. Epinephrine
• B. Aspirin
• C. Diphenhydramine
• D. Hydrocortisone

Answer: (A)

Anaphylaxis requires rapid reversal of airway swelling, bronchoconstriction, and low blood pressure, and the medication that does this fastest is epinephrine. When given promptly, epinephrine acts on multiple receptors to quickly restore breathing and circulation: alpha-1 effects constrict swollen blood vessels to raise blood pressure and reduce edema; beta-2 effects relax bronchial smooth muscle to improve airflow; beta-1 effects support cardiac output. Because of its quick, life-saving action, epinephrine is the first-line treatment in the acute setting, and it should be administered rather than waiting for slower-acting drugs. The other options may help with symptoms later or in different contexts, but they do not reverse the dangerous airway and hemodynamic changes seen in anaphylaxis. Diphenhydramine is just an antihistamine with delayed benefit for airway issues, hydrocortisone is a steroid with slow onset, and aspirin is not indicated and can be harmful in this situation.