CONTRA INDICATIONS TO METFORMIN

CONTRA INDICATIONS TO METFORMIN

            Metformin is contra indicated in patients with impaired renal function (eg. Serum creatinine ³ 1.5 mg/dl in men or ³ 1.4 mg/dl in women). In older individuals, in whom serum creatinine is not a reliable measure of renal function, metformin is contra indicated if creatinine clearance is substantially impaired. (eg. <60ml/min/1.73m²). Renal function should be checked at least yearly during metformin therapy. It is suggested that metformin be temporarily discontinued for about 48 hrs during/after use of an intravascular contrast medium until normal renal function is evidently reestablished.

            Any hypoxic state should be regarded as a contra indicated for metformin – notably chronic congestive cardiac failure, acute heart failure, severe respiratory insufficiency, septicemia and other conditions with hypoperfusion/hypoxemia significant  liver disease, history of lactic acidosis alcohol abuse or other disturbances of liver function likely to prevent normal hepatic lactate metabolism should be considered as contra indications for metformin .At present, administration of metformin is not recommended during pregnancy  or lactation because of insufficient clinical data. Metformin should be temporarily discontinued in favour of insulin administration during severe acute illnesses and major surgical procedures. Metformin is not effective as a primary treatement for type I diabetes.

Note: Metformin contra indicated in

1. Hepatic failure - chronic liver disease (SGPT ³ 3 fold above the upper limit of normal)
2. Cardiac failure - symptomatic CCF requiring pharmacological treatment.
3. Renal failure – impaired renal function (serum creatinine ³ 1.5mg/dl in men >1.4mg/dl in women) GFR < 70ml/min.
4. Respiratory failure
5. Alcohol abuse
6. Other hypoxic states
7. Contrast (iodinated) radiological procedures
8. Elderly ³ 80 years patients may be used if creatinine clearance >70ml/min
9. Type I diabetes

REFERENCE: Therapy for DM and Related Disorders, ADA