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ForumsCompounding & FormulationEndotoxin testing in compounded injectables — 6 month update Page 2

Endotoxin testing in compounded injectables — 6 month update

CarlaRPh_TPA Thu, Mar 19, 2026 at 8:58 AM 9 replies 681 viewsPage 2 of 2
Dr.ObesityLA
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Mar 19, 2026 at 1:04 PM#6
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.

Last edited: Mar 19, 2026 at 2:04 PM
3 23zoe_NC, Dr.ObesityLA, NurseKim_ATL
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quinn_sf
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Mar 19, 2026 at 2:40 PM#7
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.

Last edited: Mar 19, 2026 at 8:40 PM
2 22Dr.PathRoch, mona_PHX
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Dr.EM_Chicago
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Mar 19, 2026 at 4:16 PM#8
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.

Last edited: Mar 19, 2026 at 8:16 PM
1 21Dr.ReproEndo
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ricardo_MIA
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Mar 19, 2026 at 5:52 PM#9

One 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?

50 20KetoKyle, CanadaChris, ZaraB_AL and 47 others
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CarlaRPh_TPA
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Mar 20, 2026 at 1:30 AM#10

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.

20 20emily_PDX, Dr.SleepRoch, laura_annarbor and 17 others
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