[jordangregory]

Justing wondering why you would need to hold metformin for two days post cath. The best I can come up with is that the contrast material may mess with renal function.

[jmgrn65]

The use of the contrast and taking metformin increasing the risk of renal failure. So you were on the right track.

[dianah]

Patients who receive IV iodinated contrast (for a CT, angio, IVP, etc) are at risk for developing renal failure, called contrast-induced nephropathy (CIN).

Metformin (Glucophage) is cleared through the kidneys.
If the patient experiences renal dysfunction/failure (rising BUN, creatinine, falling eGFR) after receiving IV contrast, there can be a dangerous buildup of metformin (it isn't excreted as well by the ailing kidneys), resulting in lactic acidosis.

see the link below:
http://diabetes.emedtv.com/metformin...st-medium.html