Final answer:
Glucocorticoids are used after an initial epinephrine injection in anaphylactic reactions to inhibit late-phase allergic response and prevent related inflammation and potential health risks.
Step-by-step explanation:
Systemic glucocorticoids are used in treating anaphylactic reactions to prevent late-phase allergic reactions that can occur after the initial anaphylaxis episode. While epinephrine is the first line of defense to counteract the immediate symptoms of anaphylaxis, such as a drop in blood pressure and difficulty breathing, glucocorticoids serve to downregulate the immune response and inhibit further inflammatory processes. These steroids, including medications like prednisone, are administered after the acute phase to manage potential extended or biphasic periods of allergic response, which might not be immediately life-threatening but can still pose serious health risks if left untreated.