Which of the following oral hypoglycemic agent is preferred in obese patients?
**Core Concept**
The question requires knowledge of the pharmacological properties of oral hypoglycemic agents, specifically their effects on weight and glucose metabolism. The correct answer should be a medication that is less likely to cause weight gain or has a neutral effect on body weight.
**Why the Correct Answer is Right**
Metformin is the preferred oral hypoglycemic agent in obese patients because it does not cause weight gain and may even lead to weight loss. This is due to its mechanism of action, which involves inhibition of hepatic glucose production and improvement of insulin sensitivity. Metformin does not stimulate insulin secretion or cause an increase in appetite, making it an ideal choice for patients who are obese or at risk of weight gain.
**Why Each Wrong Option is Incorrect**
* **Option A:** Sulfonylureas, such as glimepiride, stimulate insulin secretion and can cause hypoglycemia, weight gain, and increased appetite. These side effects make them a less desirable choice for obese patients.
* **Option B:** Thiazolidinediones, such as pioglitazone, can cause weight gain and fluid retention, which may be problematic for obese patients.
* **Option D:** DPP-4 inhibitors, such as sitagliptin, may not have a significant effect on weight and can be used in obese patients, but they are not the preferred choice compared to metformin.
**Clinical Pearl / High-Yield Fact**
Metformin is often considered a first-line treatment for type 2 diabetes, especially in patients who are obese or have a history of weight gain with other oral hypoglycemic agents.
**Correct Answer:** C. Metformin