Final answer:
In the case of a patient with a score of 4 on the sedation rating scale, the nurse should first stimulate the patient.
Step-by-step explanation:
When a patient has a score of 4 on the sedation rating scale, the nurse should stimulate the patient first. Stimulation can help the patient become more alert and responsive. If the patient's condition does not improve or worsens, then the nurse should consider taking further actions such as administering naloxone, pain medication, or notifying the physician.