Which medication is primarily used to treat severe, life-threatening allergic reactions?

Explanation

Epinephrine (also known as adrenalin) is the first-line treatment for managing severe allergic reactions such as anaphylaxis. It rapidly reverses airway constriction, swelling, and low blood pressure. While corticosteroids and antihistamines may be used as adjunct therapies, they do not act as quickly or effectively in emergency situations. Diazepam, a sedative, has no role in allergy management.