Question About ML When Reconstituting Powder

Whiynot20026

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Mixing itself doesn't worry me much anymore. What still throws me off is figuring out the right ML for a peptide. With a 500MG NAD, I go with 3ML. For 10MG Reta, 1 ML works. But once it's 40MG Reta or Tirzep, that's where I get lost. I get that adding more BAC means more dilution. So shouldn't using less BAC give a more concentrated result? For a 40 gram mix, what ML would be correct?

Bill
 
The usual approach is to pick a reconstitution amount so the shot ends up at the size you prefer.

How concentrated you can go does have a ceiling, though exactly where that ceiling sits is not clearly established. When it comes to GLP, my working rule of thumb is 30mg/ml.
 
woundcarping said:

The usual approach is to pick a reconstitution amount so the shot ends up at the size you prefer.

How concentrated you can go does have a ceiling, though exactly where that ceiling sits is not clearly established. When it comes to GLP, my working rule of thumb is 30mg/ml.
Does that come out to 3 MLs? Personally, I'd rather keep the BAC amount as low as possible. Still, it's really confusing. I'm no scientist. Not yet.

Bill
 
Whiynot20026 said:

woundcarping said:

The usual approach is to pick a reconstitution amount so the shot ends up at the size you prefer.

How concentrated you can go does have a ceiling, though exactly where that ceiling sits is not clearly established. When it comes to GLP, my working rule of thumb is 30mg/ml.
Does that come out to 3 MLs? Personally, I'd rather keep the BAC amount as low as possible. Still, it's really confusing. I'm no scientist. Not yet.

Bill
When I mix, my approach is to add enough bac water so that the dose lands on a round number of units on the syringe. In other words, I try to make the needed dose equal 10u or 20u. That just makes it simple and straightforward for me to measure. It isn't always an option, but if the numbers allow it, that's the route I take.
 
Whiynot20026 said:

woundcarping said:

The usual approach is to pick a reconstitution amount so the shot ends up at the size you prefer.

How concentrated you can go does have a ceiling, though exactly where that ceiling sits is not clearly established. When it comes to GLP, my working rule of thumb is 30mg/ml.
Does that come out to 3 MLs? Personally, I'd rather keep the BAC amount as low as possible. Still, it's really confusing. I'm no scientist. Not yet.

Bill

When I mix my GLP, I generally won't go above 30mg per mL. And if I can, I like to keep the amount I inject at .3ml or less, because that fits the syringe I use most often.

With a 9mg dose, that comes to .3ml, which works for me.

To find the concentration, take the dose in mg and divide it by the mL you want the volume to be.

9mg / .3ml= 30mg/ml (dimensional analysis is a fantastic tool)

To get the reconstitution volume, divide the vial in mg by the mg/ml.

40mg vial / 30mg/ml= 1.33ml
 
woundcarping said:

Whiynot20026 said:

woundcarping said:

The usual approach is to pick a reconstitution amount so the shot ends up at the size you prefer.

How concentrated you can go does have a ceiling, though exactly where that ceiling sits is not clearly established. When it comes to GLP, my working rule of thumb is 30mg/ml.
Does that come out to 3 MLs? Personally, I'd rather keep the BAC amount as low as possible. Still, it's really confusing. I'm no scientist. Not yet.

Bill

When I mix my GLP, I generally won't go above 30mg per mL. And if I can, I like to keep the amount I inject at .3ml or less, because that fits the syringe I use most often.

With a 9mg dose, that comes to .3ml, which works for me.

To find the concentration, take the dose in mg and divide it by the mL you want the volume to be.

9mg / .3ml= 30mg/ml (dimensional analysis is a fantastic tool)

To get the reconstitution volume, divide the vial in mg by the mg/ml.

40mg vial / 30mg/ml= 1.33ml
That clears things up a lot, I appreciate it. So from what I gather, if my goal is a 2MG pep dose, then with a 40 MG vial I'd add 2ML, and that works out to 1 unit on the syringe.

Bill
 
When 2mg is split by 20mg/ml, the result is .10ml.

Using an insulin syringe for a .01ml dose is something I would almost never want to do.
 
Whiynot20026 said:

woundcarping said:

The usual approach is to pick a reconstitution amount so the shot ends up at the size you prefer.

How concentrated you can go does have a ceiling, though exactly where that ceiling sits is not clearly established. When it comes to GLP, my working rule of thumb is 30mg/ml.
Does that come out to 3 MLs? Personally, I'd rather keep the BAC amount as low as possible. Still, it's really confusing. I'm no scientist. Not yet.

Bill
https://calc.injectionshop.com/ When it comes to figuring out dosing, this calculator is the one I reach for most often. That said, plenty of others exist, and I also found reverse calculators useful for getting my head around how reconstitution and injection calculations actually work.
 
woundcarping said:

The usual approach is to pick a reconstitution amount so the shot ends up at the size you prefer.

How concentrated you can go does have a ceiling, though exactly where that ceiling sits is not clearly established. When it comes to GLP, my working rule of thumb is 30mg/ml.
Right now I'm using an R50 with a 56mg fill, mixed with 3ml, and I inject 4.3mg/43units, which comes out to 8mg.
 
BNLFL said:

woundcarping said:

The usual approach is to pick a reconstitution amount so the shot ends up at the size you prefer.

How concentrated you can go does have a ceiling, though exactly where that ceiling sits is not clearly established. When it comes to GLP, my working rule of thumb is 30mg/ml.
Right now I'm using an R50 with a 56mg fill, mixed with 3ml, and I inject 4.3mg/43units, which comes out to 8mg.
That math lines up. Appreciate it. These past few days have taught me a hell of a lot. Thanks to all of you.

Bill
 
BNLFL said:

Whiynot20026 said:

BNFL, wouldn't 30ML have worked just as well? What's the reason for 28?

Bill
What location is that?
I suppose what I asked came across as silly. The figures just struck me as odd, that's all. The reconstitution itself, though, was fine.

Bill
 
Really, quit approaching this as a concentration problem. Instead, think about picking a convenient, round volume of bac water to put into the vial.

About the injection-volume extremes: when you're drawing very small amounts, being slightly off your syringe graduation introduces more deviation from the intended dose; usually that's de minimus unless the concentration is extreme. On the flip side, 1 study reported adverse effects from a 2 ml (not unit) subcutaneous injection given in 1 pin; whether those effects last (scar tissue, for instance) isn't clear, but you're presumably far below that volume anyway.

When titrating upward, pick a plan that accommodates your step increases (for tirzepatide, usually 2.5 mg per step) so that each planned step lands on a marked number on the syringe you actually have.

Stop doing the math, ignore the standard pep calculators, and get good with the reverse calculator, anticipating that you'll recon with an odd amount of bac.

If you don't think in metric naturally, learn it thoroughly and measure twice, cut once.
 
indolent said:

Really, quit approaching this as a concentration problem. Instead, think about picking a convenient, round volume of bac water to put into the vial.

About the injection-volume extremes: when you're drawing very small amounts, being slightly off your syringe graduation introduces more deviation from the intended dose; usually that's de minimus unless the concentration is extreme. On the flip side, 1 study reported adverse effects from a 2 ml (not unit) subcutaneous injection given in 1 pin; whether those effects last (scar tissue, for instance) isn't clear, but you're presumably far below that volume anyway.

When titrating upward, pick a plan that accommodates your step increases (for tirzepatide, usually 2.5 mg per step) so that each planned step lands on a marked number on the syringe you actually have.

Stop doing the math, ignore the standard pep calculators, and get good with the reverse calculator, anticipating that you'll recon with an odd amount of bac.

If you don't think in metric naturally, learn it thoroughly and measure twice, cut once.
For the most part, I feel confident. My wife and I only recently started handling our own injections, and we've picked things up quickly. Two things still trip me up with every peptide: how to figure the dose, and how much BAC water goes into a vial. Whenever I ask people about the BAC amount, the answers are always fuzzy — nobody gives me a straight number. Does it work better to add 10ML instead of 20 ML for certain peptides, or the other way around? Personally, I want the smallest amount of BAC going into my body. It's easiest for me when the BAC drawn matches the insulin syringe at 1 mg per 10 on the needle, though I've also done 2mg per 10 units. So where's the line — when is BAC too little, and when is it too much?

Bill
 
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