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Metformin and Intravascular Contrast Media: What to do in Patients Receiving Both: a Narrative Review

Moghadaseh Shams, Pooneh Dehghan, Farhad Hosseinpanah




Metformin-associated lactic acidosis (M-ALA) is considered to be one of the complications caused by intravascular contrast media (CM) administration in diabetics especially those with coexisting renal or cardiac impairment. We focused on the necessity and duration of metformin suspension in diabetics with normal or impaired renal function scheduled for CT scan with IV contrast. Searching PubMed, Web of Science, and Scopus databases, we reviewed the latest relevant guidelines as well as articles published from 1994 to 2015. There is no global consensus among different guidelines on the duration of the Metformin suspension before CT scan with IV contrast. Also, lack of substantial evidence supporting M-ALA encourages specialists to take a less conservative approach.

It is safe to continue Metformin in patients with normal renal function who have no co-morbidities. In cases of equivocal renal function (30<GFR<60 mL/min/1.73 m2) and also in patients with normal renal function and other co-morbidities, the decision should be made based on the patient’s clinical status. In case of severe renal failure, the use of metformin should be reassessed. Due to the probability of contrast associated nephropathy, laboratory follow up seems to be necessary for all patients.


Metformin, Lactic acidosis, Contrast media, CT scan


Bailey CJ, Turner RC. Metformin. N Engl J Med. 1996;334(9):574.

Stang M, Wysowski DK, Butler-Jones D. Incidence of lactic acidosis in metformin users. Diabetes Care. 1999;22(6):925-7.

Salpeter SR, Greyber E, Pasternak GA, et al. Risk of fatal and nonfatal lactic acidosis with metformin use in type 2 diabetes mellitus. Cochrane Database Syst Rev. 2010.

Misbin RI. The phantom of lactic acidosis due to metformin in patients with diabetes. Diabetes Care. 2004;27(7):1791-3.

Kamber N, Davis WA, Bruce DG. Metformin and lactic acidosis in an Australian community setting: the Fremantle Diabetes Study. Med J Aust. 2008;188(8):446-9.

Campbell H. Worldwide Experience of Metformin as an Effective Glucose-lowering Agent: A Meta-analysis. Diabetes Metab Rev. 1995;11:S57-S62.

Eppenga WL, Lalmohamed A, Geerts AF, et al. Risk of lactic acidosis or elevated lactate concentrations in metformin users with renal impairment: a population-based cohort study. Diabetes Care. 2014;37(8):2218-24.

van Berlo‐van de Laar I, Vermeij C, Doorenbos C. Metformin associated lactic acidosis: incidence and clinical correlation with metformin serum concentration measurements. Journal of clinical pharmacy and therapeutics. 2011;36(3):376-82.

Sirtori CR, Pasik C. Re-evaluation of a biguanide, metformin: mechanism of action and tolerability. Pharmacol Res. 1994;30(3):187-228.

Misbin RI, Green L, Stadel BV, et al. Lactic acidosis in patients with diabetes treated with metformin. N Engl J Med. 1998;338(4):265-6.

Quader MA, Sawmiller C, Sumpio BA. Contrast-induced nephropathy: review of incidence and pathophysiology. Ann Vasc Surg. 1998;12(6):612-20.

Bodmer M, Meier C, Krähenbühl S, et al. Metformin, Sulfonylureas, or Other Antidiabetes Drugs and the Risk of Lactic Acidosis or Hypoglycemia A nested case-control analysis. Diabetes Care. 2008;31(11):2086-91.

Cryer DR, Nicholas SP, Henry DH, et al. Comparative outcomes study of metformin intervention versus conventional approach the COSMIC Approach Study. Diabetes Care. 2005;28(3):539-43.

Sulkin TV, Bosman D, Krentz AJ. Contraindications to metformin therapy in patients with NIDDM. Diabetes Care. 1997;20(6):925-8.

Horlen C, Malone R, Bryant B, et al. Frequency of inappropriate metformin prescriptions. JAMA. 2002;287(19):2504-5.

Khurana R, Malik I. Metformin: safety in cardiac patients. Postgrad Med J. 2010;86(1016):371-3.

Ekström N, Schiöler L, Svensson A-M, et al. Effectiveness and safety of metformin in 51 675 patients with type 2 diabetes and different levels of renal function: a cohort study from the Swedish National Diabetes Register. BMJ open. 2012;2(4):e001076.

Lalau JD, Lacroix C, Compagnon P, et al. Role of metformin accumulation in metformin-associated lactic acidosis. Diabetes Care. 1995;18(6):779-84.

Bruijstens L, Van Luin M, Buscher-Jungerhans P, et al. Reality of severe metformin-induced lactic acidosis in the absence of chronic renal impairment. Neth J Med. 2008;66(5):185-90.

Nawaz S, Cleveland T, Gaines P. Clinical risk associated with contrast angiography in metformin treated patients: a clinical review. Clin Radiol. 1998;53(5):342-4.

Parra D, Legreid AM, Beckey NP, et al. Metformin monitoring and change in serum creatinine levels in patients undergoing radiologic procedures involving administration of intravenous contrast media. Pharmacotherapy. 2004;24(8):987-93.

Radwan MA, Al Taweel ES, Al-Moghairi AM, et al. Monitoring Metformin in Cardiac Patients Exposed to Contrast Media Using Ultra–High-Performance Liquid Chromatography Tandem Mass-Spectrometry. Ther Drug Monit. 2011;33(6):742-9.

Jain V, Sharma D, Prabhakar H, et al. Metformin-associated lactic acidosis following contrast media-induced nephrotoxicity. Eur J Anaesthesiol. 2008;25(02):166-7.

Goergen SK, Rumbold G, Compton G, et al. Systematic Review of Current Guidelines, and Their Evidence Base, on Risk of Lactic Acidosis after Administration of Contrast Medium for Patients Receiving Metformin 1. Radiology. 2009;254(1):261-9.

McCartney M, Gilbert F, Murchison L, et al. Metformin and contrast media—a dangerous combination? Clin Radiol. 1999;54(1):29-33.

Maznyczka A, Myat A, Gershlick A. Discontinuation of metformin in the setting of coronary angiography: clinical uncertainty amongst physicians reflecting a poor evidence base. EuroIntervention. 2012;7(9):1103-10.

Cohan R, Dillman J, Hartman R. Amercan College of Radiology Manual on Contrast Media Version 9 ACR Manual on Contrast Media, American College of Radiology, 2013. Webpage: http://www acr org/~/media/ACR/Documents/PDF/QualitySafety/Resources/Contrast.20.

Radiologists RCo. Standards for iodinated intravascular contrast agent administration to adult patients. Published 2005, Accessed March 2009.

Owen RJ, Hiremath S, Myers A. Canadian Association of Radiologists consensus guidelines for the prevention of contrast-induced nephropathy: update 2012. Can Assoc Radiol J. 2014;65(2):96-105.

Radiologists RAaNZCo. RANZCR guideline for iodinated contrast administration. Published 2003, Accessed March 2009.

Stacul F, van der Molen AJ, Reimer P, et al. Contrast induced nephropathy: updated ESUR contrast media safety committee guidelines. Eur Radiol. 2011;21(12):2527-41.

Gruberg L, Mintz GS, Mehran R, et al. The prognostic implications of further renal function deterioration within 48 h of interventional coronary procedures in patients with pre-existent chronic renal insufficiency. J Am Coll Cardiol. 2000;36(5):1542-8.

DOI: https://doi.org/10.22037/nbm.v5i3.14850