PeptideChemSF said:The shortage clause is the answer to the second question and it is a subtraction rather than an addition.
Filing a mild objection. Mild because I might be wrong; an objection because nobody has addressed the case that does not fit. A research-chemical supplier selling lyophilised powder labelled research use only is not compounding and is not claiming to. It is a different legal universe with no pharmacy oversight, no patient relationship and no content guarantee, and conflating the two in these threads helps nobody.
CarlaRPh_TPA 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…
Beyond-use dating (BUD) for compounded supply compounded products:
Lyophilized (unreconstituted): typically 6 months from compounding date
Reconstituted with BAC water: typically 28-30 days refrigerated
Reconstituted with sterile water: typically 24 hours (no preservative!)
Always use BAC water for multi-dose vials. Sterile water has no preservative and supports bacterial growth after first puncture. This is a common and potentially dangerous mistake.
Dr.ObesityLA said:A research-chemical supplier selling lyophilised powder labelled research use only is not compounding and is not claiming to.
Compounding pharmacy customer here with experience relevant to compounded supply.
I've ordered from 4 different compounding pharmacies over the past 14 months. The quality variation is real — purity ranged from 94% to 101% of label claim based on independent Janoshik testing.
My current compounder (a 503B facility) has been consistently 98-101% purity across 8 orders. I pay $143/month vs $1,333 for brand. The savings are substantial and the product is equivalent in my experience.
Re: compounded supply — this applies whether you're using brand or compounded. The clinical principles are the same.
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Shop Reference StandardsOne thing that is still open after KristenIndy’s answer:
What actually distinguishes 503A from 503B, in terms of what each may make and from what starting material?
Closing the loop on my own question.
The bulks-list asymmetry was the piece I had missed entirely. It explains why one of my two pharmacies is still arguing it can supply and the other simply stopped.