My pharmacy stopped supplying with three weeks notice and a letter that explained nothing, so I went and read the statute.
The narrow version of the question is what actually distinguishes 503A from 503B, in terms of what each may make and from what starting material.
Numbers rather than impressions, if you have them.
Answering the narrow version, because the broad one does not have a single answer. The shortage clause is the answer to the second question and it is a subtraction rather than an addition. Both exemptions forbid compounding something that is essentially a copy of a commercially available approved product. A product FDA has listed as in shortage is not treated as commercially available, so listing removed the objection that otherwise blocked compounding. It never created a permission; it withdrew a prohibition, which is why it evaporated the moment the supply fact changed.
Happy to go further on any of that.
TrialTracker_MD said:The shortage clause is the answer to the second question and it is a subtraction rather than an addition.
Agreed, and the enforcement dates were staggered by category — 503A first, 503B a few weeks later — because outsourcing facilities have manufactured inventory and clinic contracts to unwind while a 503A makes to order.
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Shop Reference StandardsAussieAnna said:My pharmacy stopped supplying with three weeks notice and a letter that explained nothing, so I went and read the statute.
Can confirm the pattern AussieAnna describes. They are two different exemptions from the same federal requirements and they buy different things. A 503A pharmacy is regulated primarily by the state board, needs a patient-specific prescription, is exempt from CGMP, and may use a bulk substance that has a USP monograph, is a component of an approved drug, or appears on the 503A bulks list — three independent doorways. A 503B outsourcing facility registers with the FDA, is inspected on a risk basis, must comply with CGMP, may compound for office stock without a patient-specific prescription, and has one doorway to a permitted bulk substance: the 503B bulks list, or the drug shortage list.
Adding the clinical framing, because it changes how the question reads.
Compounding pharmacy licensing verification for compounded supply: before ordering, verify your pharmacy's credentials:
- State Board of Pharmacy license — check on your state BOP website
- FDA registration (for 503B) — check on fda.gov
- DEA registration if handling controlled substances
- PCAB accreditation — voluntary but demonstrates commitment to quality
- USP <797>/<800> compliance for sterile compounding
This takes 10 minutes of research and could save you from receiving substandard or unsafe medication.