Which medications should be held prior to contrast-requiring procedures/tests?

• A. Metformin
• B. Antibiotics
• C. Nephrotoxic meds (aminoglycosides, NSAIDs, vancomycin, amphotericin, tacrolimus, etc.)
• D. Insulin

Answer: (C)

Protecting kidney function around procedures that use contrast hinges on minimizing additional kidney stress. Nephrotoxic medications—such as aminoglycoside antibiotics, NSAIDs, vancomycin, amphotericin B, and tacrolimus—can worsen renal function on their own. When contrast is used, the risk of acute kidney injury increases, so pausing these agents for a short window before and after the test lowers the risk by reducing the cumulative nephrotoxic load on the kidneys. This is why holding nephrotoxic meds is the recommended approach in this scenario. Other drugs behave differently: metformin may be held in patients with reduced renal function due to lactic acidosis risk with contrast, and insulin is not routinely stopped for this reason, while many antibiotics aren’t universally held unless a specific renal toxicity risk exists.