Community β€Ί Dosing & Titration

Where oh where has my mg gone?

35 replies12 peopleMay 9, 2026β˜† Follow
Summary

why does peptide solution disappear faster than expected when using pens, cartridges, and filters during reconstitution

Users report significant volume loss across multiple vials and batches even when tracking doses carefully with pens and double-checks. The main explanations center on hold-up in 13 mm filters (around 15 units), residual liquid in tapered cartridges, and dead space in needles or syringes. Air purges or pre-wetting can recover some liquid but not all. Some also question pen accuracy or measurement habits.

What this discussion establishesWhere people disagree

whether second filtering with charged membranes actually reduces endotoxins or simply wastes product and adds risk

Still open

exact amount recoverable by air purge versus pre-wetting or flushing, and why some users still see unexplained shortfalls even after accounting for filter loss

Nothing here is advice.

35 replies Β· 12 people
PatientAlder89archiveopening postMay 9

The title captures itβ€”I can't figure out what's happening with my pen and cartridges. I mixed 2 mg bac water into 34 mg Tirz and always double-check the calculator. My husband verifies the units I'm dialing. I tracked usage and finished 25 mg from the first vial before starting the second. I prepared two cartridges one by one, filtering each. The same issue occurred with my Reta: I added 1 ml to 10 mg, made three vials sequentially. The first went up to 7 mg, but the second ran out after only 5.5 mg. No tip left in, new needle each time, so no leaks or evaporation. Anyone else seeing this?

PatientAlder89archiveMay 9
↳ replying to @SlowSignal40

Yeah I considered it myself yet the volume feels surprisingly high.

ClearCinder63archiveMay 9
↳ replying to @SlowSignal40

I remember someone mentioning that filters always keep back a little liquid. The smaller size holds roughly five portions and the bigger one holds fifteen. On top of that the holders still contain some at the finish because they narrow toward the bottom and the rod stops short of reaching it. Maybe that explains why the figures come out uneven.

PatientAlder89archiveMay 9
↳ replying to @ClearCinder63

I confirmed using the 13mm .22um filter. Hadn't noticed fifteen units still inside. The ten milligram portion measured out to forty five units while the thirty four milligram came to fifty three. It surprised me when the vial emptied after just three uses. Probably better to pick the higher concentration ones going forward, heh.

SlowSignal40archiveMay 9
↳ replying to @PatientAlder89

A comparable issue occurred for me while attempting to prepare the mixture. Fluid escaped past the filter, and because I'm so impatient, I sampled it with my tongue. Were you drawing the syringe back to send air across the filter and return the fluid to the bottle? These figures just don't add up for me. Apologies.

ClearCinder63archiveMay 9

The concentrations aren't the same at all. Did you go with matching needle specs on each?

PatientAlder89archiveMay 9
↳ replying to @SlowSignal40

That shortfall still seems odd and I feel the same way about it. I figure the other pieces probably stayed behind in the basket as well, funny how things go.

PatientAlder89archiveMay 9
↳ replying to @ClearCinder63

I remain using that identical package of those small needles. I looked into the details myself. The amount that stays behind reaches as high as twenty nine units, listed between ten and twenty nine. This accounts for much of it. The other portion likely came from the initial draw plus whatever remained inside the container.

SharpBramble33archiveMay 9

Twice I run my bottles through filters. One time targets potential non-sterile conditions, the other aims at cutting down endotoxins. My last 10mg MOTS-c left me with just 7mg once done. 😭 Yet choosing more safety beats the alternative. πŸ‘€

SlowSignal40archiveMay 9
↳ replying to @PatientAlder89

My lecture just ended so I can focus properly now. Please lay out the details clearly. A ten milligram container of Reta got mixed together using one milliliter of BAC water leaving a single milliliter solution holding ten milligrams per milliliter. What came next after that?

BlueSignal49archiveMay 9

I wonder if preparation of the pen comes before each pin for others.

PatientAlder89archiveMay 9
↳ replying to @SlowSignal40

10 mg vial, added 1 ml H-bac so 1 mg per 10 units

PatientAlder89archiveMay 9
↳ replying to @BlueSignal49

I perform that priming step solely at the start so trapped air and bubbles can escape.

PatientAlder89archiveMay 9
↳ replying to @SharpBramble33

When you filter again the second time, does that initial amount get released then? So isn't the only loss those maximum 28 units just once from the final push?

SlowSignal40archiveMay 9
↳ replying to @PatientAlder89

yes thats right. Now what happened after this reconstitution?

PatientAlder89archiveMay 9
↳ replying to @SlowSignal40

No clue here either, chuckles. Likely the filter snatched it up somehow. Still, that extra charge from the filter works out fine for me.

WarmMeadow92archiveMay 9
↳ replying to @SharpBramble33

Filtering fails to get rid of endotoxins at all. Doing it a second time just uses up materials for nothing and might introduce more impurities instead. Those toxins are way too tiny for any standard filter to catch. I've heard about special charged filters that could possibly handle them though. Are you relying on one of those? Without that, repeating the filtration step raises the chance of problems rather than lowering it.

WarmMeadow92archiveMay 9
↳ replying to @PatientAlder89

The amount lost, 45 units from those vials, exceeds what normally gets left in a filter. There could be other reasons for this. Maybe the device delivers an incorrect amount each time. Perhaps mistakes in counting the doses given out, though that seems improbable here given how straightforward the calculation is. Or possibly the tool used to measure the liquid isn't accurate, but I doubt that's it. Between those options, the initial one looks most believable to me. Which device are you employing, and did you check its accuracy?

QuietSignal61archiveMay 9
↳ replying to @SlowSignal40

That take really clicks for me. We'd probably vibe nicely together. I nibble the stalks as I load the pipe.

BlueAlder28archiveMay 9
↳ replying to @SlowSignal40

That cracked me up. The poster ought to look into ways of cutting down lost solution from the filter. Pushing air through reclaims a portion, rinsing pulls back even more, and soaking it first keeps the biggest share. The problem is most of those steps call for an added needle, though the air step skips that. Options still exist to limit extra needles, such as using a low-cost insulin syringe for the initial soak. Ordering needles by the larger lot brings the per-unit cost way down. Separately, testing the dosing device itself for consistency might be worthwhile. I once owned a unit bought online that gave erratic amounts, mostly short but now and then over. A helpful clip explains how to check the device.

SharpBramble33archiveMay 9
↳ replying to @WarmMeadow92

I wonder whether these items really do anything useful at all, above all with a budget version, yet keeping one on hand makes me feel better since there is a chance it could make some difference.

SlowTimber66archiveMay 9

The description claims it removes bacterial toxins, which got my attention. I'd want to check actual test data backing that up. It could really make a difference if it holds up.

SlowPebble39archiveMay 9

Even though I'm not relying on any injector device, I ended up missing about thirty units right after mixing for the first time. Checking online yesterday evening, the most useful explanation pointed to leftover volume inside the needle during withdrawals. Beyond that, I have no idea where those units went.

PlainAlder11archiveMay 9
↳ replying to @SlowPebble39

Perhaps the filter played a role, or an inaccurate measurement led to some loss on my part. Three milligrams seems like a significant dose.

PlainAlder11archiveMay 9

You’ll get it next time.

PatientAlder89archiveMay 9
↳ replying to @BlueAlder28

Grateful for the tip, learned about clearing extras only after counting my existing items recently. Next round I'll handle that for sure. Normally process two or three units together, though previously did extra because freezing works for this compound. Purchased a large amount so now hold more than a hundred with plenty left over. Verified multiple occasions using various amounts. Getting larger quantities sooner would likely mean greater reduction, funny enough. Thanks again!

PatientAlder89archiveMay 9
↳ replying to @SlowPebble39

It's wild this still goes down even using bottles plus needles πŸ€·β€β™€οΈ

SlowPebble39archiveMay 9
↳ replying to @PlainAlder11

Initially suspected the filter too, yet now suspect the loss might tie to those insulin syringes or the sterile vials in some manner. We split one kit between my best friend, my husband, and myself, so the three of us handled reconstitution as a group. Asked her to double-check the amounts. Because our area is fairly rural and she preferred not to carry pre-filled syringes on the drive, I measured her share for the full month, she verified it again, then I transferred everything into a fresh sterile vial. She came up ten units short and I came up twenty short. Will switch to different syringes on the next round to check whether that changes anything.

SlowPebble39archiveMay 9
↳ replying to @PatientAlder89

Yeah that matched my own thinking since my figures checked out properly though the whole thing left me puzzled.

PatientAlder89archiveMay 9
↳ replying to @SlowPebble39

This seems wild. Vapor loss might explain it? Nothing else occurs to me as another option.

PlainAlder11archiveMay 10
↳ replying to @SlowPebble39

My guess is your eyes stayed on the handle section instead of the front end while mixing the solution.

PatientSignal60archiveMay 10
↳ replying to @BlueAlder28

Does that mean running bac water across the filter first prior to putting the mixed solution through it?

BlueAlder28archiveMay 10
↳ replying to @PatientSignal60

True, that makes sense. A filter that's not moistened first would soak up the mixed peptide solution, whereas wetting it beforehand lets the solution flow through more freely since the filter takes in the liquid instead. These days I skip that step entirely along with rinsing the filter afterward. All I do now is blow air through it once finished. It's just not worth the extra effort for the small gains. No one's ever posted a comparison showing recovery rates from air blowing compared to rinsing or soaking ahead of time, though I wonder what the numbers would show.

SlowPebble39archiveMay 10
↳ replying to @PlainAlder11

I'm unsure as well. That doesn't seem right to me, given my two decades as a nurse means I'm familiar with handling these items. The filters stood out as the unfamiliar part. My close friend verified the amounts for me. The mixing day arrives soon, so I'll tweak a few aspects and check the outcome then.

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