Taking the question as asked, rather than the general version of it. Resolution therefore closed the doors unevenly, and the asymmetry follows from the bulks lists. For 503B the shortage clause was the only route to these molecules, so that route shut completely. A 503A pharmacy can still argue a doorway via "component of an approved drug" — but only for the substance in the form present in the approved product, which is exactly where the base-versus-salt argument lives, and it does nothing about the copy restriction, which came back into force on resolution.
Two pharmacies quoted me last year, one describing itself as 503A and one as 503B, and I assumed 503B just meant bigger until both stopped within weeks of each other.
What I actually want to know 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.
LabKate said:Resolution therefore closed the doors unevenly, and the asymmetry follows from the bulks lists.
LabKate has the substance of this right. The condition it depends on is worth stating. Worth adding the genuine exception, because it is real and narrow: a change made for an identified patient where the prescriber determines it produces a significant clinical difference for that patient. A grid of fixed doses offered to everybody is not that, whatever the intake form says.
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View ResultsDr.AddMedPHL said:Two pharmacies quoted me last year, one describing itself as 503A and one as 503B, and I assumed 503B just meant bigger until both stopped within…
Can confirm the pattern Dr.AddMedPHL describes. 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.
That is the short version; the long version is somebody else's post.
From the other side of the consultation, briefly.
Compounding pharmacy response time test for compounded supply: I email customer service at odd hours to test responsiveness. A pharmacy that can't answer questions promptly is a red flag.
My current pharmacy: average response time same day. They answered my questions about sterility testing thoroughly and professionally.
Communication quality is a proxy for operational quality. A pharmacy that communicates well is likely manufacturing well too.