Question about how much “liquid” to inject

longestyards

longestyards

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I’ve ordered Reta 5 mg vials. And I got bac water as well. Then I bought a bunch of 1ml syringes.

The vendor said the Reta 5mg vials are actually 2ml big. But for simplicity and my understanding, let’s say I reconstitute with just 1ml bac water. That means 10 units of the 1ml syringe is 0.5 mg Reta?

I want to start at 1mg Reta (my first time) so I would then inject myself with 20 units, right? But is it recommended to inject 20 units like that or is it too little “bac water” and I should add more bac water for reconstituting?
 
longestyards said:
I’ve ordered Reta 5 mg vials. And I got bac water as well. Then I bought a bunch of 1ml syringes.

The vendor said the Reta 5mg vials are actually 2ml big. But for simplicity and my understanding, let’s say I reconstitute with just 1ml bac water. That means 10 units of the 1ml syringe is 0.5 mg Reta?

I want to start at 1mg Reta (my first time) so I would then inject myself with 20 units, right? But is it recommended to inject 20 units like that or is it too little “bac water” and I should add more bac water for reconstituting?
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Your math is correct for using 1ml of BAC water.

Since you are new at this, I would recommend using more BAC water which will help achieve more accurate dosing (I would aim for at least 1.5ml, or preferably 2ml). Once you become more comfortable with reconstitution and dosing, you can adjust the fluid volume lower, although personally I like aiming for around .2ml to .25ml for each dose.

One of the sponsoring vendors has a nice calculator that might help as well: https://calc.injectionshop.com/
 
ZippityDooDah said:
Your math is correct for using 1ml of BAC water.

Since you are new at this, I would recommend using more BAC water which will help achieve more accurate dosing (I would aim for at least 1.5ml, or preferably 2ml). Once you become more comfortable with reconstitution and dosing, you can adjust the fluid volume lower, although personally I like aiming for around .2ml to .25ml for each dose.

One of the sponsoring vendors has a nice calculator that might help as well: https://calc.injectionshop.com/
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Thank you so much for answering.

I asked an llm and it said I should reconstitute with 5ml and inject myself with 1ml for 1mg. But now that you say 0.2-0.25 ml is enough, then I guess it’s insane to inject 1ml?

Is there any difference to injecting with more watered out reconstitution?
 
longestyards said:
Thank you so much for answering.

I asked an llm and it said I should reconstitute with 5ml and inject myself with 1ml for 1mg. But now that you say 0.2-0.25 ml is enough, then I guess it’s insane to inject 1ml?

Is there any difference to injecting with more watered out reconstitution?
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Injecting 1ml isn't "insane" but it's pretty excessive and really unnecessary most of the time.

Most brand-name dosing is in the .2ml-.5ml range. With certain peptides a larger water volume can help avoid ISRs, pain/stinging, etc., but for reta a 1ml dose is too much.

By adding more water, you're giving yourself a larger margin for error. Using your original 1ml reconstitution water volume, if your dosage draw is off by an easily plausible +/- .01ml that will result in a 10% dosage error, where with 2ml water volume you cut that error to 5%.
 
1 ml is 1cm³. The official Mounjaro-pens in Europe are 0,6ml per full dose. So I try not to go beyond this.
 
I encourage you to learn about third party testing, which can reveal overfill. When that's substantial it's a good practice to use the tested mass rather than what the vendor says is in the vial.

A reverse calculator is helpful at that point. I use one always, which might be unnecessarily fussy
 
BNLFL said:
The vials are 2ml, not 3? They contain 5mg of Reta?
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According to the vendor, yes. But it might actually be 3mL, because their bac waters you can get in 3mL or 10ml sizes which would suggest the 5mg Reta should be in 3mL sizes. But I think the vendor knows. I’ll report back in 2-4 weeks if I get it.
 
longestyards said:
According to the vendor, yes. But it might actually be 3mL, because their bac waters you can get in 3mL or 10ml sizes which would suggest the 5mg Reta should be in 3mL sizes. But I think the vendor knows. I’ll report back in 2-4 weeks if I get it.
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3ml, not 30ml?
 
longestyards said:
The vendor said the Reta 5mg vials are actually 2ml big.
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Do you mean 2mg big? If so than that's a 40% overfill.

Huge difference between mg and ml as one ml of H20 has a mass of 1000mg

You should be doing your calculation based upon a 7mg vial.

I also recommend doing your calculations both backwards and forwards until you get comfortable with the units.
 
Also might be worth getting 0.3 mL (vs 1mL) syringes, since the dosing marks are further apart, giving you more precision and control over the exact volume of liquid.

A thought I have (and a bit of a counter-point to what others are saying, once someone has been researching for a bit): Dosing errors do start to smooth themselves out a bit over time. For the very first dose, drawing up 10% too much means 10% too much in the RS. Once you're a month or two in (at a constant dose), drawing up 10% too much only means 5% too much in the RS. To unpack that, on the first dose, RS has 0mg in their system before injecting 1mg so the full error is experienced. After a month or so RS has 1mg (left over from previous dosing) before injecting 1mg more. In that case drawing up 10% extra would lead to 2.1 total in the system, which is only 5% more than desired.

Of course, that goes out the window if you're making the exact same 10% error every week. This can happen when someone is confused on what part of the plunger to line up with the marks on the syringe, so make sure you read the documentation on that. Improperly reading volume is also a common mistake made by students in general chemistry labs everywhere when using graduated cylinders. 😉
 
Firstly, welcome!

Injection Shop calculator is the BEST. It is the only one that turned on my dosing lightbulb. It gave me the confidence to finally order.

The vial you will receive is likely a 3ml vial. It will hold up to 3ml of reconstituted solution (powder + bac water).

If your vendor told you the vials are 2mg over, that's an overfill. The mass (mg) of the product is confirmed by testing. As you move forward, ask vendors for their CoA (typically Janoshik). Check the testing date; it should be within 3 mos of when you purchase (buying now, Dec 25 would be as far back I as I would consider tested batch) Look for the VERIFICATION CODE at the bottom and then check it.

Always test at least for mass and purity. Vendor CoA is never the reliable source. Many are out of date or they may not test the product you want to purchase.

In the meantime, there are testing groups you can join. You can also test a vial of the product yourself. There are a few US labs in addition to Janoshik (EU): Freedom and PeptideTest.com

PeptideTest also has a step by step filtering video on YT. Let me find the link for you.

(Edited to make it clear vendor CoA is not gospel)
 
Turbo-Farmer said:
Do you mean 2mg big? If so than that's a 40% overfill.

Huge difference between mg and ml as one ml of H20 has a mass of 1000mg

You should be doing your calculation based upon a 7mg vial.

I also recommend doing your calculations both backwards and forwards until you get comfortable with the units.
Click to expand...
The vendor said the vial is 2ml big. But the Reta amount is 5mg in that vial.
 
tubby said:
Also might be worth getting 0.3 mL (vs 1mL) syringes, since the dosing marks are further apart, giving you more precision and control over the exact volume of liquid.

A thought I have (and a bit of a counter-point to what others are saying, once someone has been researching for a bit): Dosing errors do start to smooth themselves out a bit over time. For the very first dose, drawing up 10% too much means 10% too much in the RS. Once you're a month or two in (at a constant dose), drawing up 10% too much only means 5% too much in the RS. To unpack that, on the first dose, RS has 0mg in their system before injecting 1mg so the full error is experienced. After a month or so RS has 1mg (left over from previous dosing) before injecting 1mg more. In that case drawing up 10% extra would lead to 2.1 total in the system, which is only 5% more than desired.

Of course, that goes out the window if you're making the exact same 10% error every week. This can happen when someone is confused on what part of the plunger to line up with the marks on the syringe, so make sure you read the documentation on that. Improperly reading volume is also a common mistake made by students in general chemistry labs everywhere when using graduated cylinders. 😉
Click to expand...
I will be targeting 1mg reta so it’s not so bad if it’s 1.1 or 0.9 if I reconstitute with 1-2ml o thought
 
longestyards said:
I will be targeting 1mg reta so it’s not so bad if it’s 1.1 or 0.9 if I reconstitute with 1-2ml o thought
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I mean I personally wouldn't care and I personally target ~10unit doses and do all sorts of other things that aren't best practices. LOL

We're just giving you best practices here since you asked. 🙂
 
longestyards said:
I will be targeting 1mg reta so it’s not so bad if it’s 1.1 or 0.9 if I reconstitute with 1-2ml o thought
Click to expand...
Check your math multiple times,

There's no way to tell If your a super responder to Reta or not.

I'm still at a low dose of triz. I want to go up, but I still experience nausea for a few hours after.
 
BNLFL said:
Pretty sure he meant the 5mg Reta he bought came to him in 2ml vials, not 3ml like normal.
He mentioned that's what the vendor told him.
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That’s exactly what I meant!
tubby said:
I mean I personally wouldn't care and I personally target ~10unit doses and do all sorts of other things that aren't best practices. LOL

We're just giving you best practices here since you asked. 🙂
Click to expand...
Yes that’s what I am looking for. I just mentioned what I was thinking to give context to my questions but I will definitely follow the tips you’ve given instead.
HereKittyKitty said:
Firstly, welcome!

Injection Shop calculator is the BEST. It is the only one that turned on my dosing lightbulb. It gave me the confidence to finally order.

The vial you will receive is likely a 3ml vial. It will hold up to 3ml of reconstituted solution (powder + bac water).

If your vendor told you the vials are 2mg over, that's an overfill. The mass (mg) of the product is confirmed by testing. As you move forward, ask vendors for their CoA (typically Janoshik). Check the testing date; it should be within 3 mos of when you purchase (buying now, Dec 25 would be as far back I as I would consider tested batch) Look for the VERIFICATION CODE at the bottom and then check it.

Always test at least for mass and purity. Vendor CoA is never the reliable source. Many are out of date or they may not test the product you want to purchase.

In the meantime, there are testing groups you can join. You can also test a vial of the product yourself. There are a few US labs in addition to Janoshik (EU): Freedom and PeptideTest.com

PeptideTest also has a step by step filtering video on YT. Let me find the link for you.

(Edited to make it clear vendor CoA is not gospel)
Click to expand...
thank you so much for this information! It is super helpful!



BNLFL said:
OP, use this. I'd do the 5mg vial, then .05ml BAC then syringe size, then your dose you want and see what you get. You can play around from there.
Click to expand...
Thanks I’ll use this.
 
longestyards said:
I will be targeting 1mg reta so it’s not so bad if it’s 1.1 or 0.9 if I reconstitute with 1-2ml o thought
Click to expand...
This is backwards thought, which is why the reverse calculator is your friend, and the regular one has no real purpose for us.

Use an awkward amount of bac at reconstitution and an exact rationally-determined number of units with each jab.

Don't try to do math.
 
My thoughts on this are to do the calculation both ways.

-first reverse to find what you want to dose.

- and then forward to check your work with another calculator.

In my industry this is essential, as concentrations vary and supplies come in many different sizes. If you do a high and a low calculation, and then take into consideration your materials, you often find the sweet spot where everything lines up
 
So, is the 3ml the most common syringe for reconstituting and filtering?
 
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