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c/coldchain·posted 6 months ago by u/zeynep_ndiaye

the excursion thing finally clicked for me and I want to write it down

Discussion Receipts ×2 Cold Box ×3 Clean Column ×3

Confession thread, sort of.

I went from 2.5mg to 1.0mg much faster than I should have because the scale had stalled and I got impatient. The stall broke about 3 weeks later, at which point I had no way of knowing whether the dose increase did anything or whether it would have broken anyway.

So now I have constipation I did not need and a data point I cannot interpret. Two lessons in one.

Posting it in the hope that somebody at week 72 reads it before doing the same thing.

2,742 up / 137 down95% upvoted32 commentsid 1trwbw26 Jan 2026

32 comments

28 in this archive, depth 5

best — the order this archive was captured in

u/emeka_delgado214 points·6 months ago

Water content matters more than people think. If a vial is carrying residual moisture, your "10mg" is not 10mg of peptide.

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u/cato_batista146 points·6 months ago

Titration speed is a side-effect dial far more than an efficacy dial.

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u/zeynep_ndiayeOP310 points·6 months ago

Logger trace from my shipment: 4 hours at 15°C. Powder tested 97.6% against 97.9% claim. Tolerates more than the box implies.

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u/spain_receta238 points·6 months ago

Logger trace from my shipment: 4 hours at 15°C.

Adding to this: lyophilised is doing more work than the comment implies.

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u/marta_ilunga115 points·6 months ago

a warm courier van is a bigger problem for a mixed vial than for dry powder

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u/cesar_teixeira163 points·6 months ago

Strongly agree. Peak temperature is not the whole story.

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u/rohan_steiner123 points·6 months ago

excursion claims need a logger trace or a photo at unboxing, not "it felt warm"

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u/ms_fragmenter104 points·6 months ago

The practical rule people converge on is 28 days at fridge temperature after first puncture, and that comes from the preservative, not the peptide.

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u/usb_logger_ursulaMOD80 points·6 months ago

This is an urgent-care question wearing a forum question's clothes. Please contact a clinician rather than waiting for replies.

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[removed]29 points·6 months ago

[removed by moderator]

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u/rohan_steiner35 points·6 months ago

Denmark to Denmark takes 5 days on average, variance is 12 days

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u/fatima_yildiz24 points·6 months ago

gel packs last 23 hours, after that you are relying on the box itself

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u/marta_ilunga10 points·6 months ago

Edit to your parent would help — the concentration you quoted assumes one scenario and you have written another above it.

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u/nightowl_injector23 points·6 months ago

Edit to your parent would help — the concentration you quoted assumes one scenario and you have written another above it.

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u/aleksi_eriksen52 points·6 months ago

time-at-temperature integral is the dose, not just peak temperature

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u/zeynep_ndiaye44 points·6 months ago

This is correct. Dry powder is way more robust than liquid.

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u/zeynep_ndiayeOP16 points·6 months ago

This is correct.

Counter-anecdote: opposite result, same dose. Which mostly tells us the variance is huge.

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u/sterile_field_steph0 points·6 months ago

Inter-lab variance on this kind of assay is routinely 1–2 points. Different column, different gradient, different integration.

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u/amara_dziedzic1 point·6 months ago

Logger trace from my shipment: 20 hours at 35°C. Powder tested 97.6% against 97.9% claim. Tolerates more than the box implies.

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u/anya_salgado1 point·6 months ago

gel packs last 18 hours, after that you are relying on the box itself

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u/britt_okwuosa1 point·6 months ago

Yeah, data logger is the only acceptable proof.

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u/kenji_demir1 point·6 months ago

Reconstituted or dry powder?

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u/zeynep_ndiayeOP1 point·6 months ago

stability after excursion is not zero, it is dose-dependent

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u/intent_to_treat15 points·6 months ago

I love that this community will spend 40 comments on a detail. That pedantry is why the numbers here matter.

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u/fatima_yildiz4 points·6 months ago

Yeah, data logger is the only acceptable proof.

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u/plain_titration_20242 points·6 months ago

Not to be pedantic but packaging and stability are being used interchangeably and they are not interchangeable in real life.

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u/priya_guerrero12 points·6 months ago

Crossposting this to c/tapering because the people who need it are not reading this community.

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u/curious_panel_only4 points·6 months ago·edited

lane reports need origin, destination, carrier, and actual transit days

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About c/coldchain

Temperature and stability in the real world: what an excursion actually costs you, why lyophilised powder is far more forgiving than reconstituted solution, how to read a logger CSV, and how to photograph a failed shipment so the conversation with the vendor is short.

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  1. Excursion claims need a logger trace or a photo taken at unboxing. "It felt warm" is not data.
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