Oral hypoglycemic which causes cholestatic jaundice-
**Core Concept**
Troglitazone, a thiazolidinedione (TZD), was the first oral hypoglycemic agent to be withdrawn from the market due to its rare but serious side effect of causing cholestatic jaundice. This condition is characterized by a reduction in bile flow, leading to an accumulation of bilirubin and subsequent liver dysfunction.
**Why the Correct Answer is Right**
Troglitazone induces cholestatic jaundice by causing a reduction in bile flow, which is thought to be due to its effects on the intrahepatic bile ducts. The exact mechanism is not fully understood, but it is believed to involve the inhibition of bile salt export pumps (BSEP) in the liver. This can lead to a buildup of bile salts in the liver, causing damage and inflammation.
**Why Each Wrong Option is Incorrect**
* **Option A:** Metformin, another oral hypoglycemic agent, does not cause cholestatic jaundice. Instead, it is associated with lactic acidosis, a rare but serious side effect.
* **Option B:** Sitagliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor, is not known to cause cholestatic jaundice. It is generally well-tolerated and has a low risk of adverse effects.
* **Option C:** Pioglitazone, a thiazolidinedione (TZD) similar to troglitazone, does not cause cholestatic jaundice. However, it is associated with an increased risk of heart failure and fractures.
**Clinical Pearl / High-Yield Fact**
Troglitazone's withdrawal from the market highlights the importance of monitoring liver function in patients taking oral hypoglycemic agents. Other agents in this class, such as pioglitazone, should be used with caution in patients with pre-existing liver disease.
**Correct Answer:** C. Pioglitazone