Myself Dr Josh- and I’m happy to help with your question today.
Well, It is advised that one should stop Metformin before CT scan.
The contrast (a fluid that helps the radiologist read the CT picture) given prior to the procedure may cause kidney problems in patients who take Metformin. It is recommended that he should stop Metformin the day before you take the contrast for the CT scan.
I understand that your father has accidentally taken diabetes medication.
Iodinated contrast could impair renal function and therefore he could not appropriately excrete the metformin /metabolites causing an extremely unusual condition lactic acidosis.
Though such condition is very rare.
Usually, he can go for the test, but it has to be discussed with his doctor.
He should Drink lots of water and stay hydrated to eliminate the contrast.
It would be a good idea to call your primary care doctor to check in.
He should take plenty of fluids at this time.
I would suggest, that you can call his doctor and discuss this issue.
Hope this helped
If you have any further question then you can ask me.
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