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ForumsCompounding & FormulationCompounded peptide reconstitution water — what worked for you? Page 2

Compounded peptide reconstitution water — what worked for you?

tane_welly Wed, Mar 11, 2026 at 3:34 AM 8 replies 817 viewsPage 2 of 2
PeptideChemSF
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Mar 11, 2026 at 9:49 AM#6
JennaRN said:
Dead space is the answer to the missing dose.

I am going to disagree with reconstituting low as a general rule. More diluent, more punctures, more in-use days at room temperature, and the stability trade-off is real. Precision is not the only variable being optimised.

I would rather be corrected than agreed with, if it comes to it.

Last edited: Mar 11, 2026 at 1:49 PM
27 22steve_okc, dave_SLC, FDA_TrackerJim and 24 others
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PharmacoVig_BOS
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Mar 11, 2026 at 12:16 PM#7

Adding the numbers, since they settle part of this. Two things anyone can check: a state licence number for a 503A, and an FDA outsourcing-facility registration for a 503B. Both are publicly searchable, and a pharmacy unwilling to give you either has answered the question.

Ask again with the specifics and you will get a better answer than this one.

26 21Dr.GutHealth, amsterdam_pete, LondonLisa and 23 others
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Dr.RaviCardio
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Mar 11, 2026 at 2:43 PM#8
PeptideChemSF said:
I am going to disagree with reconstituting low as a general rule.

There is a second half to this that has not been said yet. They are two different exemptions from the same federal requirements and they buy different things. A 503A pharmacy is regulated primarily by the state board, needs a patient-specific prescription, is exempt from CGMP, and may use a bulk substance that has a USP monograph, is a component of an approved drug, or appears on the 503A bulks list — three independent doorways. A 503B outsourcing facility registers with the FDA, is inspected on a risk basis, must comply with CGMP, may compound for office stock without a patient-specific prescription, and has one doorway to a permitted bulk substance: the 503B bulks list, or the drug shortage list.

Last edited: Mar 11, 2026 at 3:43 PM
25 20mark_tokyo, hans_munich, jason_sac26 and 22 others
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chris_chi24
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Mar 11, 2026 at 5:10 PM#9

Following on from wendy_avl — and this may be the naive question:

How to check the arithmetic without trusting a website calculator, since three calculators gave me three answers?

24 19PurityPaulOR, MaxMetOK, MounjBrad and 21 others
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tane_welly
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Mar 12, 2026 at 4:56 AM#10

OP back with an update, since a thread like this is useless without one.

Follow-up: it was dead space. Switching to a low-dead-space fixed-needle syringe gave me the tenth dose back.

Last edited: Mar 12, 2026 at 7:56 AM
14 14pam_columbus, nick_SD_fit, ben_calgary and 11 others
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