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

When you pick up a generic pill at the pharmacy, you might not think about what makes it legal to sell—or why it works just like the brand-name version. That’s where 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 Therapeutic Equivalence Evaluations, it's the official guide that tells pharmacists and doctors which generics can safely replace brand-name drugs. This isn’t just paperwork—it’s what keeps your prescriptions affordable and your health safe.

The FDA Orange Book doesn’t just list drugs. It connects them. For every approved medication, it shows the active ingredient, the brand name, the patent numbers, and whether a generic version has been rated as therapeutically equivalent. That rating—usually marked as "AB"—means the generic works the same way in your body. No guesswork. No risk. If a drug doesn’t have an AB rating, it might not be interchangeable. That’s why your pharmacist checks this book before swapping your prescription. It’s also why companies can’t just slap a generic label on a drug and call it the same. They have to prove it matches the original in strength, how fast it gets into your blood, and how long it lasts. This is called bioequivalence, and it’s the core of the entire system.

Behind the scenes, the FDA Orange Book tracks patent expirations and exclusivity periods. This is where things get tricky. Some brand-name companies try to delay generics by filing new patents on minor changes—like switching from a pill to a liquid. The Orange Book exposes these moves, so regulators and competitors can challenge them. That’s why antitrust lawsuits often reference this database. It’s also why you see new generic versions pop up right after a patent expires. The system isn’t perfect, but without this book, you’d have no way to know if your $5 generic is truly equal to the $100 brand.

You’ll find entries here for everything from blood pressure meds like losartan to antibiotics like amoxicillin. The book also includes discontinued drugs, so you can track what’s no longer available. And while it’s mostly used by professionals, you can access it online for free. If you’re trying to save money on meds, knowing how to read the Orange Book helps you ask the right questions. Is there a generic? Is it rated AB? Why isn’t my pharmacy offering it? These aren’t just technical questions—they’re financial ones.

Below, you’ll find real-world stories and guides that tie directly into how the FDA Orange Book shapes your access to medicine. From how pay-for-delay deals block generics to how biosimilars are changing the game, these posts show you how this quiet database affects your health, your wallet, and your choices every single day.