cory_ATX said:They are two different exemptions from the same federal requirements and they buy different things.
Compounding pharmacy customer here with experience relevant to compounded supply.
I've ordered from 3 different compounding pharmacies over the past year. 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 6 orders. I pay $130/month vs $1,280 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.
One thing that is still open after Dr.ReproEndo’s answer:
What actually distinguishes 503A from 503B, in terms of what each may make and from what starting material?
DanielChem_CHI said:Compounding pharmacy customer here with experience relevant to compounded supply.
Compounded has been just as effective for me. If compounded supply is the concern, the COA from my 503B pharmacy shows 99.1% purity. Verified by Janoshik.
Sigma-Aldrich — Research-Grade Standards
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Shop Reference StandardsOP back with an update, since a thread like this is useless without one.
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.
DebRD_ATL said:Compounded has been just as effective for me.
Agreeing with DebRD_ATL, and the qualification matters more than the agreement. 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.