Question

Lactic acidosis is more likely to be caused by which one of the following drugs?

• A. Gliclazide
• B. Acarbose
• C. Metformin
• D. Pioglitazone

Hint:

Think about which antidiabetic drug changes how cells make energy and raises lactate.

Answer 1

The Correct Option is C

This question checks which antidiabetic drug carries the risk of lactic acidosis, a build up of lactate that can turn dangerous fast.

1. Gliclazide: A sulfonylurea that makes the pancreas release more insulin. Its main danger is hypoglycemia, not lactic acidosis.
2. Acarbose: Blocks sugar breakdown in the gut. It gives gas and loose stools, nothing to do with lactate.
3. Metformin: Cuts liver glucose output and shifts cells toward using glucose without oxygen, which raises lactate. When the kidneys cannot clear it, as in renal impairment, lactate piles up and causes lactic acidosis.
4. Pioglitazone: Acts on PPAR gamma, causing fluid retention and weight gain. It is not tied to lactic acidosis.

Metformin is the answer because it is the only drug here that changes how cells make energy in a way that raises lactate, and this effect turns dangerous when the kidneys cannot clear the drug.

Let's summarize:

• Metformin lowers liver glucose output and increases anaerobic glucose use, raising lactate.
• Renal impairment lets metformin build up, which is why lactic acidosis is a known risk with this drug.

So the drug most likely to cause lactic acidosis is metformin.