Drug Facts: TZDs

Pioglitazone (Actos) and Rosiglitazone (Avandia) are part of the drug class called thiazolidinesdiones, or TZDs for short. They work by decreasing insulin resistance and decreasing how much glucose is being produced in the liver. You may not notice a significant improvement in your blood sugar readings at first as they can take 8-12 weeks or more to work.

These drugs can really help lower blood sugars, but they also come with some serious side effects. These include fluid retention, possibly leading to heart failure in people at risk, as well as an increased risk of bone fractures. There is also debate whether Avandia may contribute to heart attack. Avandia is still on the market, but rarely prescribed because of this. Weight gain is also a side effect of this drug, which is also true for other diabetes drugs like sulfonylureas and insulin.