Scenario
- Metformin is safe to use in chronic kidney disease (CKD) when the eGFR is greater than 30ml/min.
- Diuretics are often needed for volume control in CKD.
- If your CKD patients are on metformin and a diuretic consider giving them the following advice:
"If your vomiting, diarrhoea or fever last longer than 24 hours do not take your metformin and diuretics and contact your GP for possible same day review."
(If the patient has concomitant heart failure you may just withhold metformin and continue the diuretic.)
Blood pressure and diabetes control are the cornerstones of management of diabetic kidney disease. As patients age they are at increased risk of acute kidney injury. To reduce the risk of metformin associated lactic acidosis and renal damage you should educate your patients to withhold metformin and diuretics and seek medical review in the event of a dehydrating illness.
Medications may be restarted when the acute illness has resolved.
