Context: The prevalence of diabetes markedly increased in recent decades. It is well accepted
that the risk of morbidity and fatality increases in patients with type 2 diabetes (T2DM).
Evidence Acquisition: An electronic search was performed to detect suitable studies, with
keywords of metformin, prediabetes, diabetes Mellitus, Gentamicin and lactic acidosis.
Results: Metformin (biguanide) is widely used as the first pharmacological option in
pre-diabetic subjects and patients with T2DM. Low-cost, long-term effect, low risk of
hypoglycemia, and ease in utilization are considered as significant benefits of metformin
compared with other therapies. Numerous studies have explored that medicinal
intervention particularly metformin administration not only can decrease high blood
glucose in patients with T2DM but also can avoid or postpone the beginning of clinical
T2DM in pre-diabetic cases. Protective effect of metformin on renal cells by different
mechanisms is described here. Gentamicin is an important factor that affects kidney
function and structure. Nephrotoxicity is one of the serious side effects of gentamicin
(an aminoglycoside antibiotic). Numerous investigation showed the protective effect of
metformin against the gentamicin nephrotoxicity. On the other hand, lactic acidosis is
known as an uncommon but serious side effect of metformin that should be mentioned.
Signs of lactic acidosis are defined by plasma lactate levels higher than 5 mmol/L and pH
smaller than 7.4.
Conclusions: Different small series and large experimental investigations have discovered
the association between metformin and lactic acidosis summarized here.