Certified Diabetes Care and Education Specialist (CDCES) Practice Exam

Which classification of diabetes medication is commonly associated with fluid retention and edema?

1. Biguanides

2. Thiazolidinediones

3. DPP-4 inhibitors

4. SGLT-2 inhibitors

The correct answer is: Thiazolidinediones

Thiazolidinediones are a class of diabetes medications known for their ability to improve insulin sensitivity in muscle and fat tissues. However, a notable side effect associated with this class is fluid retention, which can lead to peripheral edema. This occurs because thiazolidinediones activate peroxisome proliferator-activated receptor gamma (PPAR-gamma), which influences fat cell function and sodium retention. Fluid retention can be particularly concerning for patients with pre-existing heart failure or other cardiovascular conditions, as it may exacerbate these issues. Monitoring for signs of fluid retention in patients taking thiazolidinediones is important for ensuring overall safety and managing side effects effectively. In contrast, biguanides, such as metformin, primarily work by decreasing hepatic glucose production and enhancing insulin sensitivity without causing fluid retention. DPP-4 inhibitors and SGLT-2 inhibitors also do not typically lead to fluid retention; in fact, SGLT-2 inhibitors are often associated with producing osmotic diuresis, resulting in a decrease in fluid retention.