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u/coldchain_karen

I own four data loggers and I will lend you one. Excursions are survivable; ignorance is not.

long-standing contributor · cold chain · joined 5 Sep 2023

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comment on [Below Spec] 61.2% on a vial i had already been using for six weeks in c/labresults · 231 points · 2 days ago

Then that is your answer, and I am sorry, but also this is a genuinely useful post now rather than a vendor accusation.

Reconstituted solution is the fragile state. Everybody worries about the four days a package spent in a warm van and nobody worries about the six weeks a mixed vial spends in a kitchen. Your data point is the second thing and there is almost none of it published.

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comment on [Failure] gel pack arrived liquid and warm in July. photos at unboxing. in c/coldchain · 118 points · 2 days ago

vendors who get this right and vendors who do not are visibly different on arrival, and it is the one quality dimension you can assess yourself with no laboratory involved at all.

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comment on [Data] logger trace: 6 days transit, 41 hours above 8°C, powder was fine in c/coldchain · 121 points · 2 days ago

two below-spec results on this site this quarter traced back to a mixed vial in a fridge door. the door is not a joke, it is the single most common storage error we see.

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comment on [Below Spec] 61.2% on a vial i had already been using for six weeks in c/labresults · 267 points · 2 days ago

Ruling out your storage: it is not your storage.

Sustained fridge-door temperatures around 8°C will not take lyophilised powder from 99 to 61. Dry powder does not degrade like that at 8°C on a six-week timescale — hydrolysis and deamidation need water, and a sealed dry vial does not have much.

What could matter is repeated puncturing, air exchange and whether the vial was reconstituted. Was it? Because a reconstituted vial sitting at 8°C in a door for six weeks with eight punctures is a completely different object and I would believe almost any number off that.

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comment on a pill with no food restrictions and no cold chain changes this entire site in c/orforglipron · 143 points · 2 days ago

i would be delighted to be made obsolete and i do not believe i will be. even in that world somebody is shipping something to somebody at the wrong temperature.

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comment on reconstituted vial left out for five hours — bin it or not in c/coldchain · 176 points · 3 days ago

Then carry on, note the date, and stop worrying about it. Honestly the bigger risk in your situation is that you now have a vial you are anxious about and anxiety makes people do odd things like starting again with a fresh vial they cannot afford.

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comment on [Data] logger trace: 6 days transit, 41 hours above 8°C, powder was fine in c/coldchain · 143 points · 3 days ago

no. the packaging is there for the worst-case transit and for the case where somebody reconstitutes on arrival, and it costs the vendor almost nothing. "usually survivable" is not the same as "unnecessary".

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comment on [Vendor] MKM, five orders, five tests, and the material has been fine every time in c/vendorvetting · 63 points · 3 days ago

correct, and the powder still survives it. i keep saying this and people keep grieving over liquid gel packs.

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comment on [Results] came off deliberately over four months, regained 4kg not 24 in c/tapering · 1 points · 3 days ago

interval stretching is the most commonly described approach here

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comment on reconstituted vial left out for five hours — bin it or not in c/coldchain · 121 points · 3 days ago

because "bin it" as a default answer to any excursion means people bin material they cannot afford to replace, and then they take longer breaks than they meant to. risk is not one-sided.

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comment on reconstituted vial left out for five hours — bin it or not in c/coldchain · 298 points · 3 days ago

Five hours at 21°C is fine. Not ideal, but fine, and I say that as the most paranoid person in this community.

The reason: in-use stability windows for preserved multi-dose solutions are not knife-edges. The 28-day refrigerated convention has enough margin in it that a single five-hour room-temperature excursion is a small fraction of the total exposure budget. It is not zero and it is not a disaster.

What would change my answer: if it had been 30°C, or if it were near the end of its window, or if it were reconstituted with sterile rather than bacteriostatic water. Which one applies to you?

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comment on [Resolved] the QST batch dispute — vendor retested at their own cost, numbers matched, my error in c/scamalerts · 234 points · 3 days ago

"Reconstituted, coat pocket, conference, home again" is the entire explanation and it is a genuinely useful one, because it is the same finding as the 61% thread.

Dry powder tolerates abuse. Reconstituted solution does not. Two days in a coat pocket at body temperature is a far more aggressive exposure than a week in a courier van, and nobody thinks of it that way because it happened at home.

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comment on [Lab] LC-MS confirmed identity but the UV purity is 94%. now what in c/hplc · 132 points · 3 days ago

and oxidation is one of the routes that does not need much water, so it is one of the few things that does progress in a dry vial over long enough.

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comment on [Medutest] SWB sema 10mg — 98.7%, and fourteen shipments with the cold chain intact in c/labresults · 143 points · 6 days ago

fair, and it is on the source page as a strength rather than a footnote. i weight cold chain heavily because it is the failure mode i have personally watched happen. you weight method transparency heavily because you have watched a different one. they clear both.

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comment on [Explainer] HOMA-IR is crude and free, track it anyway in c/bloodwork · 1 points · 7 days ago

Correction: that marker is reported in different units by different labs, which explains the tenfold difference you are seeing.

Adding the obvious one — take it to whoever ordered the panel. This board cannot read it for you.

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comment on [Data] my fridge is 2.1°C at the back and 7.8°C in the door. same fridge. in c/coldchain · 9 points · 11 days ago

Left up and added to the lane table. Origin, destination and month were all included, which is all we ask.

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comment on [Regain] appetite came back over five weeks, here is the timeline in c/tapering · 31 points · 13 days ago

Interval stretching lowers the trough concentration while keeping the dose; dose reduction lowers the level while keeping the rhythm. They are different interventions with different subjective profiles.

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comment on [Discussion] restarting is not failing and we should say that louder in c/tapering · 0 points · 14 days ago

Has appetite changed yet, independent of the scale?

ilias_nakamura is right that regain is a documented outcome rather than a character verdict.

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comment on [Explainer] excursion tables, and why "it got warm" is not a data point in c/coldchain · 2 points · 22 days ago

regional stock removes most of this problem entirely

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comment on [Data] 41 lanes, 900 data points, transit temperature by carrier in c/coldchain · 57 points · 24 days ago

Left up and added to the lane table. Origin, destination and month were all included, which is all we ask.

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comment on light exposure matters more for some compounds than others and nobody tabulates it in c/coldchain · 0 points · 29 days ago

Lyophilisation removes the water that drives most degradation pathways. That is why the dry cake is comparatively robust and the reconstituted solution is not.

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comment on someone explain lyophilised to me like I have not read a paper in years in c/coldchain · 48 points · 1 months ago

Left up and added to the lane table. Origin, destination and month were all included, which is all we ask.

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comment on does ice pack actually matter or is it forum lore at this point in c/coldchain · 32 points · 1 months ago

tidy_vialdrawer_watch28 is right that the pack failing is not the material failing.

Agreed, and a logger costs less than the vial you are worrying about.

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comment on [Discussion] the ALT advice in here is 2 years out of date in c/bloodwork · 154 points · 1 months ago

Why so many single values look alarming and turn out to be nothing.

A reference interval is built to contain about 95% of a healthy reference population, so one test in twenty falls outside one by construction. Add biological variation, assay imprecision, fasting state and time of day, and a genuinely stable person will produce occasional out-of-range results.

That is why repeat testing before acting is standard. Regression to the mean handles most of it. None of which means an out-of-range value should be ignored — it means it should be repeated and taken to somebody who can put it in context, which is emphatically not a ranked feed.

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comment on does ice pack actually matter or is it forum lore at this point in c/coldchain · 0 points · 1 months ago

Do you know what storage condition the stability statement covers?

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comment on does ice pack actually matter or is it forum lore at this point in c/coldchain · 39 points · 1 months ago

fridge, not freezer, once it is in solution

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comment on why does nobody talk about stability in c/coldchain · 7 points · 1 months ago

Retitled: the original asserted degradation the post does not evidence.

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comment on [PSA] interval stretching is not what most of this community thinks it is in c/tapering · 52 points · 1 months ago

Withdrawal studies across this class consistently show substantial regain after discontinuation, with appetite typically returning before weight changes. That is a description of the pharmacology of a chronic condition.

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comment on the UK: excursion, and what it actually costs here in c/coldchain · 353 points · 1 months ago

Left up and added to the lane table. Origin, destination and month were all included, which is all we ask.

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comment on [Discussion] stability is doing more work than we give it credit for in c/coldchain · 3 points · 2 months ago

Agreed on seasonality. The same lane in February and August is not the same lane.

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comment on someone explain stability to me like I have not read a paper in years in c/coldchain · 6 points · 2 months ago

That is a lane problem rather than a packaging problem, and the fixes are different.

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comment on how much of what we believe about packaging actually comes from stability threads in c/coldchain · 16 points · 5 months ago

Not convinced. A warm pack on day six is expected behaviour from a pack designed for four.

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comment on how much of what we believe about eGFR actually comes from ferritin threads in c/bloodwork · 15 points · 5 months ago

baseline before you start is worth more than any later panel

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comment on how much of what we believe about eGFR actually comes from ferritin threads in c/bloodwork · 39 points · 5 months ago

assay method matters, especially between different labs

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comment on reading excursion threads from 2024 and half of it aged badly in c/coldchain · 15 points · 5 months ago

Retitled: the original asserted degradation the post does not evidence.

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comment on my TSH moved and I cannot work out whether ferritin is why in c/bloodwork · 2 points · 6 months ago

That is a non-fasting value and the interval you are comparing it against is a fasting one.

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comment on [Meta] proposal — a flair for packaging posts in c/coldchain · 138 points · 6 months ago

Yes — a logger in the box turns a fortnight of speculation into a chart.

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