Metformin must be held for how many hours before and after iodinated contrast?

Metformin must be held for how many hours before and after iodinated contrast?

• A. 24
• B. 72
• C. 48
• D. 96

Answer: (C)

Holding metformin around the time iodinated contrast is given is about preventing accumulation if kidney function dips after contrast exposure. Iodinated contrast can transiently impair renal function, and metformin is cleared by the kidneys. If clearance is reduced, metformin can build up and, in rare cases, contribute to lactic acidosis. To minimize this risk, the medication is paused for a window around the procedure. The standard guidance is to hold metformin for roughly two days around the contrast—i.e., stop on the day of imaging and continue for about 48 hours after. Metformin can be resumed once kidney function has recovered and baseline creatinine/eGFR is reestablished. This 48-hour window balances safety with minimizing unnecessary disruption to diabetes management. Shorter holds could miss a period of reduced clearance if kidney function declines, while longer holds unnecessarily delays glycemic control.

Holding metformin around the time iodinated contrast is given is about preventing accumulation if kidney function dips after contrast exposure. Iodinated contrast can transiently impair renal function, and metformin is cleared by the kidneys. If clearance is reduced, metformin can build up and, in rare cases, contribute to lactic acidosis. To minimize this risk, the medication is paused for a window around the procedure.

The standard guidance is to hold metformin for roughly two days around the contrast—i.e., stop on the day of imaging and continue for about 48 hours after. Metformin can be resumed once kidney function has recovered and baseline creatinine/eGFR is reestablished. This 48-hour window balances safety with minimizing unnecessary disruption to diabetes management. Shorter holds could miss a period of reduced clearance if kidney function declines, while longer holds unnecessarily delays glycemic control.