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c/coa·posted 4 months ago by u/liv_nkemelu

COA: what the trials say vs what this community says

Lab Well Actually ×3 Clean Column ×1 Receipts ×1

Been lurking in c/tirzepatide for about 22 months and finally have something worth posting.

Short version: week 69, 1.7mg, and water content is the bit I still cannot get a straight answer on. I have read the wiki, I have read the last 15 threads, and the answers split roughly down the middle.

What I actually want to know is whether the people saying it does not matter have measured it, or whether it is just repeated confidently. Happy to be told I am overthinking this — I probably am — but I would rather overthink it now than at week 63.

5,253 up / 666 down89% upvoted43 commentsid y1doxn27 Mar 2026

43 comments

25 in this archive, depth 6

best — the order this archive was captured in

u/first_hundred-11 points·4 months ago

no "is this good?" without saying what the compound and claimed purity are

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u/dario_boateng1 point·4 months ago

You have restated the marketing copy. What is the actual substance here.

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u/liv_nkemeluOP0 points·4 months ago

No. This is the kind of confident post that gets copied into a screenshot and repeated for years. Where is the evidence.

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u/liv_nkemeluOP1 point·4 months ago

Tested the GLB raw material and a reseller vial side-by-side. Same purity claim, different impurity profiles. Handling matters.

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u/marisol_frisk660 points·4 months ago

the counterion is part of the mass you paid for

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u/rohan_steiner193 points·4 months ago·edited

no "is this good?" without saying what the compound and claimed purity are

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u/yusuf_nakamura310 points·4 months ago

Cosigning. The batch number is load-bearing information.

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u/tomas_lehtinen213 points·4 months ago

the batch number or it did not happen

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u/sig_figs_sammod · analytical161 points·4 months ago

purity and net content are two different numbers, same vial

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u/nadia_fonseca193 points·4 months ago

Half-life is about 168 hours, so steady state lands around week 13–5. Practical consequence: what you feel in week 1 is not what that dose does.

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u/freya_baptista51 points·4 months ago

axis labels included, always

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u/honest_syringe24453 points·4 months ago

What is the method line say? Not the technique, the actual method.

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u/vito_chowdhury252 points·4 months ago

Dead space in the needle hub holds a small but non-trivial volume. On low-volume draws that can be several units.

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u/liv_nkemeluOP108 points·4 months ago

Asked SGN for the batch-specific COA and they sent it within six hours, full document, batch number, date, everything. That is the baseline.

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u/neha_erdogan0 points·4 months ago

What is the method line say? Not the technique, the actual method.

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u/wrong_network_w1 point·4 months ago

area% is not mass%, and here is exactly why it matters

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u/sig_figs_sammod · analytical1 point·4 months ago

area% is not mass%, and here is exactly why it matters

Yes, exactly this, and it is the bit that took me 10 weeks to accept.

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u/dario_boateng1 point·4 months ago

Water content on the document? That affects your concentration math.

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[deleted]1 point·4 months ago

[deleted]

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u/honest_syringe2474 points·4 months ago

post the whole document, not the headline number

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u/karma_irrelevant32 points·4 months ago

You have restated the marketing copy. What is the actual substance here.

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u/cesar_ivaturi205 points·4 months ago·edited

Yeah, 96.8% area is not the problem, the missing impurity breakdown is the problem.

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u/janek_ferrari49 points·4 months ago

chromatogram or it did not happen

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u/hugo_bergstrom22 points·4 months ago

Yeah, 96.8% area is not the problem, the missing impurity breakdown is the problem.

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u/nabila_espinoza365 points·4 months ago

Cosigning. The batch number is load-bearing information.

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About c/coa

How to read a certificate of analysis and what it does and does not tell you. Area% versus mass%, identity versus quantity, water content, related substances, acetate counterions, and the difference between a vendor-supplied COA and an independent test on the vial you actually received.

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