Do not take metformin for 48 hours prior to surgery.



Metformin (1,1-dimethyl-biguanide) is a biguanide derivative used in the management of diabetic conditions such as non-insulin-dependent diabetes mellitus (type 2) and especially in the treatment of patients with moderate or pathological overweight (pre-obesity/obesity).

Metformin lowers the blood sugar level through various mechanisms. It is one of the antidiabetics longest in use. Medical studies have confirmed that the regular use of metformin reduces the risk of cardiovascular conditions in type 2 diabetes patients.

A serious potential side effect of metformin, which may occur during anaesthesia, is lactic acidosis, a condition characterized by the excessive accumulation of lactic acid (lactate) in the blood. The mortality in patients with metformin-associated lactic acidosis is up to 30%.

Therefore, it is vital that metformin be discontinued two days prior to surgery.

Before you have an operation, please contact your primary care doctor or diabetologist to find out whether your diabetes medication contains metformin. During the pre-op consultation, inform the anaesthetist in detail about your medications to avoid any complications during surgery.

Please check the list below (not exhaustive) for information on metformin-based medications:

Diabetase, Glucophage, Mediabet, Meglucon, Mescorit, Met, Metfogamma, Thiabet, Biocos, Diabesin, Glucobon, Siofor, Metformin-ratiopharm, Metformin-Stada and other generics.


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