Which of the following steps is essential before administering medications in emergency response?

Before administering medications in an emergency response scenario, checking for allergies is essential. Understanding a patient's allergy history is crucial because administering a medication to a patient with a known allergy can result in severe, potentially life-threatening reactions. This step ensures the safety of the patient and helps prevent complications that could arise from an allergic reaction.

Knowing the patient's allergies allows the healthcare provider to make informed decisions about which medications can be given safely. While verifying the patient's identity, determining medication history, and assessing vital signs are all important components of patient care, they do not have the immediate impact on safety that checking for allergies has in this context. In emergency situations where time is often of the essence, ensuring that the medication does not trigger an allergic response can be lifesaving.