503A vs 503B compounding pharmacies: what the difference means for you
“Compounded” covers two very different kinds of pharmacy, named after the sections of federal law that govern them.
503A: traditional compounding pharmacies
- Compound for an individual patient on a prescription.
- Regulated mainly by state boards of pharmacy.
- Not required to follow the full manufacturing quality standard (cGMP) that drug makers follow, though they must meet compounding standards set by USP.
- Can only use bulk ingredients that meet specific federal criteria, which is why peptides such as BPC-157 cannot be compounded today.
503B: outsourcing facilities
- Register with FDA, are inspected by FDA, and must follow cGMP.
- Can produce larger batches without a patient-specific prescription, mostly for clinics and hospitals.
- Have tighter limits on which bulk ingredients they may use. They had to stop compounding tirzepatide and semaglutide from bulk once the shortages ended.
Neither type is “FDA-approved.” Approval applies to drugs, not pharmacies, and compounded drugs are not FDA-approved.
Questions worth asking your provider
- Which pharmacy fills my prescription, and in which state is it licensed?
- Does the pharmacy test each batch for potency and sterility, and can I see a certificate of analysis?
- Is the active ingredient the base molecule or a salt form? FDA has raised concerns about salt forms in compounded GLP-1s.
- How is the medication shipped and kept cold?
A provider that answers these plainly is a good sign. We note pharmacy type for every provider in our price table.
Safety information
Compounded medications are not FDA-approved and have not been evaluated by FDA for safety, effectiveness, or quality. GLP-1 medications carry risks including nausea, pancreatitis, gallbladder disease, and a boxed thyroid warning. Only a licensed clinician can decide what is appropriate for you.
Sources
- fda.gov/drugs/human-drug-compounding/information-503b-outsourcing-facilities
- fda.gov/drugs/human-drug-compounding/section-503a-federal-food-drug-and-cosmetic-act
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