What action should the nurse take if a client on antibiotics shows signs of an allergic reaction?

When a client on antibiotics exhibits signs of an allergic reaction, the most immediate and critical action the nurse should take is to stop the antibiotic infusion. This step is crucial because continuing to administer the drug can worsen the patient's reaction, which may lead to severe complications, including anaphylaxis. Quickly discontinuing the source of the allergic reaction is vital for patient safety and allows for other necessary interventions to be implemented effectively.

While monitoring vital signs, administering antihistamines, and documenting the reaction are important parts of the overall management of an allergic reaction, they follow the urgent need to halt further exposure to the allergen. In allergic reactions, especially those involving medications, prioritizing patient safety by stopping the potentially harmful agent takes precedence.