A client is scheduled for a CT with and without contrast to rule out diverticulitis. Which medication on the client’s medication list would be of concern to the nurse?

Number 3 is correct.

Metformin should be held before and up to 48 hours afterward when radiologic studies require the use of IV contrast dye due to the increased risk of acute renal failure or lactic acidosis. None of the other medications are contraindicated with IV contrast dye.