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ForumsCompounding & FormulationEndotoxin testing in compounded injectables — LAL vs rFC methods Page 4

Endotoxin testing in compounded injectables — LAL vs rFC methods

LabKate Sat, Jun 6, 2026 at 12:43 AM 17 replies 423 viewsPage 4 of 4
GenomicsKate
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Jun 7, 2026 at 9:11 PM#16
SleepDoc_PDX said:
Compounding pharmacy customer here with experience relevant to compounded supply.

This is my experience too, for whatever a second data point is worth. Posting only so the count is not one.

Last edited: Jun 8, 2026 at 2:11 AM
32 5DebRD_ATL, KristenIndy, MarkLI_maint and 29 others
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paul_denver
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Jun 8, 2026 at 2:27 AM#17
josh_phd_bmore said:
I have been on both brand and compounded, and in the context of compounded supply, my experience has been equivalent with both.

Genuinely useful, thank you. I had the facts and not the framework. Sending this to two other people who asked me the same thing last week.

Last edited: Jun 8, 2026 at 8:27 AM
33 6jason_paloalto, Dr.LeslieOBGYN, MikeNYC_runner and 30 others
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Dr.SleepRoch
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Jun 8, 2026 at 7:44 AM#18

From the other side of the consultation, briefly.

503A vs 503B compounding pharmacies for compounded supply — this distinction matters enormously:

Feature503A503B
RegulationState Board of PharmacyFDA-registered
PrescriptionRequired (patient-specific)Can compound without patient Rx
TestingVaries by statecGMP required
ScaleSmall batchesLarger production
Quality consistencyVariableGenerally higher

I strongly recommend 503B facilities. The FDA oversight and cGMP requirements mean more consistent product quality.

Last edited: Jun 8, 2026 at 11:44 AM
34 7Dr.NephBHM_UK, kim_atl_prep, sarah_TO and 31 others
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lucas_SP_BR
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Jun 8, 2026 at 1:01 PM#19
Dr.SleepRoch said:
503A vs 503B compounding pharmacies for compounded supply — this distinction matters enormously: Feature 503A 503B Regulation State Board of Pharmacy…

Adding a me-too, because a thread of one person's experience is not much use. I had assumed I was the exception until I read this.

35 8KarenAZ_mom, zoe_NC, Dr.ObesityLA and 32 others
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Admin
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Jun 8, 2026 at 6:18 PM#20

Moderator note: leaving this open. It is being argued well and the disagreement is the useful part. Thread quality here is what the rules are for. Keep it up.

Last edited: Jun 8, 2026 at 10:18 PM
7 5PeptideSynthNJ, Dr.KarenChen, Dr.NateNeph and 4 others
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