Which medication is associated with lactic acidosis as a potential adverse effect?

Which medication is associated with lactic acidosis as a potential adverse effect?

• A. Metformin (Glucophage)
• B. Glyburide, Glipizide, Chlorpropamide
• C. Topiramate (Topamax)
• D. Ritalin, Dexedrine (ADHD)

Answer: (A)

Lactic acidosis is a known serious adverse effect linked to metformin because, in addition to lowering hepatic glucose production, metformin inhibits mitochondrial respiration. This can increase lactate production and reduce its clearance, especially when kidney function is reduced, volume depletion occurs, there is hypoxia, or when contrast dye is used and renal function is compromised. Among the options, metformin is the one most strongly associated with lactic acidosis. The other drugs listed are associated with other adverse effects—sulfonylureas mainly risk hypoglycemia, topiramate can cause a non‑anion gap metabolic acidosis but not classically lactic acidosis, and ADHD stimulants have different systemic effects without the lactate-accumulation mechanism.

Lactic acidosis is a known serious adverse effect linked to metformin because, in addition to lowering hepatic glucose production, metformin inhibits mitochondrial respiration. This can increase lactate production and reduce its clearance, especially when kidney function is reduced, volume depletion occurs, there is hypoxia, or when contrast dye is used and renal function is compromised. Among the options, metformin is the one most strongly associated with lactic acidosis. The other drugs listed are associated with other adverse effects—sulfonylureas mainly risk hypoglycemia, topiramate can cause a non‑anion gap metabolic acidosis but not classically lactic acidosis, and ADHD stimulants have different systemic effects without the lactate-accumulation mechanism.