Final answer:
Before administering intravenous chemotherapy, the nurse should administer an antiemetic to help prevent nausea and vomiting.
Step-by-step explanation:
Before administering intravenous chemotherapy to the patient being treated, the nurse should administer an antiemetic. An antiemetic is a medication that helps prevent and control nausea and vomiting, which are common side effects of chemotherapy. By giving the patient an antiemetic before starting the chemotherapy, the nurse can help reduce the likelihood of these side effects and make the treatment more tolerable for the patient.