People with kidney, liver or heart problems may not want to take metformin because it can cause a rare but sometimes fatal condition called lactic acidosis. This is more common in people with kidney, liver or heart problems. This can occur because of metformin accumulating in the body and is fatal in approximately 50 percent of cases. Lactic acidosis occurs in a number of different conditions, including type 2 diabetes. People who drink a lot of alcohol or are elderly may be at higher risk. Let your doctor know if you have had a stroke, heart attack or high blood pressure.
Metformin may cause diabetic ketoacidosis, which is a medical emergency. Metformin hydrochloride is not recommended for children under 10 years of age.Do not take metformin if you are allergic to any of the ingredients. Do not take if you drink alcohol to excess, whether on a regular basis or occasionally. If you have type 1 diabetes, this drug will not be the right medication for you. If you are having diagnostic imaging where contrast media are injected, you will be asked to stop taking metformin before the procedure. The same instructions may apply to surgery. If you are pregnant or breast-feeding, you should not take metformin. Some other medications and supplements may interact with metformin. Let your doctor know if you are taking other medications or supplements.