Why is it important to know a patient's allergies before administering IV medication?

Understanding a patient's allergies before administering IV medication is crucial primarily because it is essential for preventing potential allergic reactions. Allergic reactions can range from mild symptoms, such as rashes and itching, to severe reactions like anaphylaxis, which can be life-threatening. Knowing a patient's allergies allows healthcare providers to avoid administering medications that could trigger such responses, ensuring the patient's safety.

Selecting appropriate intravenous equipment, expediting medication administration, or determining fluid preferences do not directly relate to the risk of allergic reactions. While these factors are important aspects of IV therapy, they do not prioritize patient safety in the same way as identifying allergies does. The essential focus should always be on preventing adverse reactions that could compromise the patient's health.