Medicinal and toxic causes of lactic acidosis:
ii.alcohols and glycols (ethanol, ethylene glycol, methanol, propylene glycol)
iii.antiretroviral nucleoside analogs (zidovudine, didanosine, lamivudine)
iv.beta-adrenergic agents (epinephrine, ritodrine, terbutaline)
v.biguanides (phenformin, metformin)
vii.cyanogenic compounds (cyanide, aliphatic nitriles, nitroprusside)
viii.sugars and sugar alcohols (fructose, sorbitol, and xylitol),
xiii.diethyl ether, 5-fluorouracil
Metformin is an oral anti-diabetic drug in the biguanide class.
It is the first-line drug of choice for the treatment of type 2 diabetes, particularly in overweight and obese people and those with normal kidney function
When prescribed appropriately, metformin causes few adverse effects—the most common is gastrointestinal upset—and, unlike many other anti-diabetic drugs, does not cause hypoglycemia if used alone.
Lactic acidosis can be a serious concern in overdose.
Metformin helps reduce LDL cholesterol and triglyceride levels and is not associated with weight gain, and is the only anti-diabetic drug that has been conclusively shown to prevent the cardiovascular complications of diabetes.
Reference: KD Tripathi’s Pharmacology,6th ed.,p-268 [Table 19.2]