Which of the following is a priority nursing action for a patient in pain?

Administering pain medication per the order is the priority nursing action for a patient in pain because it directly addresses the patient’s immediate need for relief. Pain can significantly impact a patient's physical and emotional well-being, affecting their vital signs, response to treatment, and overall recovery process. By prioritizing the administration of pain relief, the nurse ensures that the patient's discomfort is managed promptly, which is fundamental to providing competent and compassionate care.

While documenting the pain level, checking vital signs, and involving family members can be important aspects of holistic patient care, they do not directly alleviate the patient’s pain. Immediate intervention with medications is necessary to enhance the patient's comfort level and support their overall health outcomes. Thus, the administration of ordered pain medication is the most critical action in this situation.