The FDA maintains the most comprehensive and authoritative drug database in the United States. Every approved prescription drug, every approved generic, every licensed biologic and biosimilar — it is all in the FDA's publicly accessible databases. Here is a complete guide to finding what you need.
The FDA Orange Book: Your Primary Generic Lookup Tool
The Approved Drug Products with Therapeutic Equivalence Evaluations — universally called the Orange Book — is the FDA's definitive list of:
- All FDA-approved brand name drugs
- All approved generic equivalents
- Therapeutic equivalence codes (AB = substitutable, BX = not demonstrated equivalent, etc.)
- Patent and exclusivity information for brand name drugs
How to search the Orange Book:
1. Go to fda.gov/drugs/drug-approvals-and-databases/orange-book
2. Search by active ingredient, brand name, or applicant (manufacturer)
3. Review the list of approved generic manufacturers
The Orange Book uses therapeutic equivalence codes. The most important: AB-rated generics are considered therapeutically equivalent to the brand and can be substituted by a pharmacist in most states.
The FDA Purple Book: Biosimilar Database
For biological products (biologics), the FDA publishes the Purple Book — formally the Lists of Licensed Biological Products with Reference Product Exclusivity and Biosimilarity or Interchangeability Evaluations.
The Purple Book lists:
- All licensed reference biological products (the branded biologics)
- All approved biosimilars and their interchangeability status
- Exclusivity periods
Interchangeable biosimilars (the highest FDA designation) can be substituted by a pharmacist without physician intervention — the same way AB-rated generics can be substituted.
FDA Authorized Generics: A Special Category
An authorized generic is a brand name drug sold under a generic label by the same manufacturer or a licensed partner — without going through the ANDA approval process. Authorized generics are chemically identical to the brand (they literally come from the same manufacturing line) but are sold at a lower price.
Key facts about authorized generics:
- They are approved under the brand drug's New Drug Application (NDA), not a separate ANDA
- They do not count as the "first generic" for 180-day generic exclusivity purposes
- They are listed in the FDA's Authorized Generic Drug List, published quarterly
- They are often introduced to compete with the first independent generic and maintain market share
For patients: authorized generics are functionally identical to brand name drugs and fully exempt from the 2026 tariff. They appear in the FDA's authorized generic database and often show up on GoodRx as the lowest-priced option.
How to Search FDA Approved Drugs
For general FDA drug searches:
Drugs@FDA — The main FDA drug approval database. Search by brand name, generic name, or active ingredient. Shows approval dates, applications, and supplemental approvals. Access at: fda.gov/cder/daf/
DailyMed — National Library of Medicine resource (FDA data). Provides complete drug label (package insert) for every approved drug. Search at dailymed.nlm.nih.gov.
FDA Drug Shortage Database — If your pharmacy can't fill your prescription, check the FDA drug shortage database at fda.gov/drugs/drug-safety-and-availability/drug-shortages.
FDA Prescription Drug Pricing Data
The FDA does not publish drug prices directly — that is CMS's domain (see NADAC). However, the FDA's drug databases connect to pricing information in several ways:
- NDC codes from the Orange Book connect to NADAC pricing records
- Orange Book patent expiry dates tell you when generics will become available
- Authorized generic listings help identify lower-cost alternatives immediately
RxTariff combines FDA drug label data (via OpenFDA) with CMS NADAC pricing data to give you both in one lookup. Use the drug search tool to search any drug and see FDA-sourced classification alongside government pricing data.
FDA Generic Drug Requirements: What Gets Approved
For a generic drug to receive FDA approval (ANDA):
1. Bioequivalence demonstrated — typically via pharmacokinetic studies in healthy volunteers
2. Same active ingredient, form, strength, and route as the reference brand
3. Inactive ingredients (excipients) reviewed — they can differ from the brand, but must be safe
4. GMP compliance — the manufacturing facility must pass FDA inspection
5. Labeling matches the brand's approved labeling (with minor adjustments)
FDA-approved generic drugs are not lower quality. They undergo a rigorous review process — the abbreviated pathway just skips the clinical trials because the brand drug already proved safety and efficacy.