The antidiabetic agents most likely to cause lactic acidosis is:
## **Core Concept**
The question tests knowledge on the side effects of various antidiabetic agents, specifically focusing on the risk of lactic acidosis. Lactic acidosis is a serious complication that can arise from the use of certain medications. It is crucial to understand the pharmacological profiles of different antidiabetic drugs to identify which ones are more likely to cause this condition.
## **Why the Correct Answer is Right**
Metformin, a biguanide, is the correct answer because, although it is not commonly associated with lactic acidosis, the risk is higher compared to other options listed, especially in patients with risk factors such as renal impairment. The mechanism behind metformin-induced lactic acidosis involves its effect on mitochondrial complex I, which leads to an increase in anaerobic metabolism and subsequently an increase in lactate production.
## **Why Each Wrong Option is Incorrect**
- **Option A:** This option is incorrect because sulfonylureas, like glyburide, primarily cause hypoglycemia as a side effect, not lactic acidosis. They work by stimulating insulin release from the pancreatic beta cells.
- **Option B:** This option is incorrect as thiazolidinediones (TZDs) or glitazones are more commonly associated with side effects like fluid retention, heart failure, and hepatotoxicity, not lactic acidosis.
- **Option D:** This option is incorrect because DPP-4 inhibitors, such as sitagliptin, generally have a favorable side effect profile, with a low risk of causing significant metabolic disturbances like lactic acidosis.
## **Clinical Pearl / High-Yield Fact**
A key point to remember is that while metformin is the correct answer, the risk of lactic acidosis is significantly increased in patients with renal impairment. Therefore, assessing renal function before starting metformin and monitoring it regularly is a crucial clinical practice. The classic scenario for lactic acidosis with metformin involves a patient with acute kidney injury or severe chronic kidney disease.
## **Correct Answer:** .