A 75-year-old patient with pneumonia and a history of hypertension and diabetes is scheduled for a CT scan with contrast. What medications should the nurse recognize as nephrotoxic and which action should the nurse prioritize to minimize the risk of acute kidney injury.

Novolog and Lantus insulin. Instruct the patient to fast for at least 12 hours prior to the scan.

Flagyl and Metformin. Obtain a baseline serum creatinine level after the procedure.

Vancomycin and IV contrast dye. Administer a dose of metformin as ordered before the procedure.

Gentamicin and Metformin. Administer IV fluids to ensure adequate hydration before the procedure.