Based on the symptoms described (facial swelling, hives, trouble breathing, wheezing, and tachycardia), it suggests that the child is experiencing an allergic reaction, specifically anaphylaxis. Anaphylaxis is a severe and potentially life-threatening allergic reaction.
In such cases, the first-line medication that the nurse would expect to administer is epinephrine (also known as adrenaline). Epinephrine is the primary treatment for anaphylaxis as it helps to counteract the allergic response by constricting blood vessels, improving breathing, and reducing swelling. Epinephrine is typically administered via an auto-injector device, such as an EpiPen, into the thigh muscle.