FDA Orange Book: What It Is and Why It Matters for Generic Drugs

When you pick up a generic pill at the pharmacy, you’re relying on the FDA Orange Book, a public database maintained by the U.S. Food and Drug Administration that lists approved drug products with therapeutic equivalence evaluations. Also known as Approved Drug Products with Therapeutic Equivalence Evaluations, it’s the go-to source for knowing which generics are legally interchangeable with brand-name drugs. Without it, pharmacies couldn’t safely swap out expensive brand drugs for cheaper versions—your wallet and your doctor would both be guessing.

The FDA Orange Book doesn’t just list drugs. It tracks patent listings and exclusivity periods for each medication. That’s how you know why a generic version of a drug might be available one month but not the next. Some drugmakers file secondary patents on minor changes—like a new coating or dosage form—to delay generics. The Orange Book exposes these moves so regulators and consumers can see when real competition is coming. It’s the legal backbone behind every price drop you see on your prescription.

But it’s not just about cost. The Orange Book also tells you which generics are therapeutically equivalent—meaning they work the same way in your body as the brand. That’s the "AB" rating you might see on your prescription label. If a generic has an "AB" rating, you can swap it with confidence. If it’s "BX," the FDA says there’s not enough proof it works the same. This isn’t theory—it’s daily practice in pharmacies across the country. And it’s why posts here cover topics like secondary patents, drug exclusivity, and how companies delay generics. The Orange Book is the map behind all of it.

What you’ll find below are real-world stories about how these rules affect patients, prices, and treatment choices. From how patent tricks keep drug costs high to how you can spot a truly interchangeable generic, these articles break down the system that’s quietly shaping your health care. You’re not just reading about drugs—you’re learning how to navigate the system that decides which ones you get, and at what price.