Quick answer
FDA-approved drugs undergo product-specific premarket review for safety, effectiveness, and quality. Compounded drugs are prepared for particular circumstances under federal and state requirements but are not FDA-approved and do not undergo that premarket review. They are not automatically generic equivalents.
Key takeaways
- ✓Compounded drugs are not FDA-approved.
- ✓A compounded drug is not the same legal category as an approved generic.
- ✓503A and 503B describe different compounding pathways, not quality ratings.
- ✓The exact pharmacy, formulation, concentration, and instructions matter.
01
FDA review is product-specific
FDA-approved drugs undergo premarket review based on evidence and manufacturing information for specific labeled uses. Drugs@FDA contains most approved prescription and over-the-counter drug products.
02
Compounded drugs are not FDA-approved
FDA states that compounded drugs do not undergo its premarket review for safety, effectiveness, or quality. Compounding can meet an individual patient need in some circumstances, but a compounded drug is not automatically a generic equivalent of an approved product.
03
Questions for a provider
Ask for the exact product, why compounding is being considered, the dispensing pharmacy, and the clinician’s monitoring plan. Regulatory availability can change, so date every answer.
04
FDA-approved, generic, and compounded are different
An FDA-approved brand or generic product is reviewed through an approval pathway tied to a defined product. An approved generic must satisfy statutory requirements that include demonstrating therapeutic equivalence to its reference product. A compounded drug is prepared under a different legal framework and is not approved by FDA.
That distinction matters in advertising. Describing a compounded product as “the generic version” or simply “the same” as an approved medicine can obscure differences in review, formulation, packaging, concentration, and labeling.
05
What 503A and 503B mean
Section 503A generally concerns qualifying compounding by state-licensed pharmacies or physicians based on prescriptions for identified individual patients. Section 503B allows qualifying outsourcing facilities to register with FDA and compound under a different set of conditions. Registration as an outsourcing facility does not turn a compounded drug into an FDA-approved product.
A directory should record the pharmacy name and stated type only when supported by an appropriate source. It should not use “503A” or “503B” as a blanket safety endorsement.
06
Why formulation and dosing details matter
Compounded products can vary in concentration, container, inactive ingredients, and administration instructions. FDA has reported dosing errors with compounded injectable semaglutide, including confusion involving units, milligrams, concentrations, and multidose vials. Consumers should receive clear instructions from the prescriber and dispensing pharmacy and should not improvise dosing.
Common questions
Frequently asked questions
Are compounded drugs FDA-approved?
No. FDA does not conduct premarket review of compounded drugs for safety, effectiveness, or quality.
Is a compounded drug the same as a generic drug?
No. An FDA-approved generic meets a statutory approval standard; a compounded drug is not FDA-approved.
Does 503B mean FDA-approved?
No. A 503B outsourcing facility may register with FDA and operate under specific requirements, but its compounded products are not thereby FDA-approved.
Primary sources
- About Drugs@FDAU.S. Food and Drug Administration · checked July 20, 2026
- Compounding and the FDA: Questions and AnswersU.S. Food and Drug Administration · checked July 20, 2026
- FDA’s Concerns with Unapproved GLP-1 Drugs Used for Weight LossU.S. Food and Drug Administration · checked July 20, 2026
- Compounding Risk AlertsU.S. Food and Drug Administration · checked July 20, 2026