Final answer:
In the event of an error in administration of medication, the nurse should be notified first.
Step-by-step explanation:
In the event of an error in administration of medication, the nurse should be notified first. The nurse is responsible for administering medication to the patient, and they are trained to handle any issues or errors that may occur. They can assess the situation, provide immediate care if needed, and then inform the doctor and pharmacist if necessary.