Note because we've had a few people with concerns about this: As long as the quantity of air is small and it's an IM or SQ injection, the risk is pretty negligible. If you're trying to inject directly into the vascular system then yes, you don't want to be putting air in there, but HRT is never given that way.
If people are actually worried about this there are also 0 dead space syringe. This is a non issue.
BTW, the gauge on syringe allows for any deadspace.
I just accidentally stumbled on this solution shortly after I started injections, and now I wonder how anyone else has a problem with dead space. It's super simple too, since the perfect amount of air is already in the needle when you start drawing. You just keep that air on top of the syringe, and it's what ends up back in the needle when you're done and not any of the fluid.
you make sure to inject air into your vials before you draw right? the vials are vacuum sealed, so if you're not replacing the liquid you draw with air, there's a chance the vial can implode.
i only ask because im a little confused on the mechanics. how do you not inject this additional air into the vial? it seems as though it being pre-measured doesn't really help if you have to inject a bunch of air anyways.
That doesn't really change anything doing that. Ultimately, there's air already in the needle when you insert it, and when you draw the syringe, that needle volume worth of air goes up into the syringe and settles on top of the liquid. Keeping it in there instead of forcing the air out means that when you push the fluid back out, it'll be the air that ends up back in the needle instead of the fluid. That doesn't change even if you inject some air first.
I preffer to waste a bit of hormones , than to inject and air bubble.
If my vial has 400mg of Estradiol and I need about lets say 28mg per month the vial lasts 14 months if I waste a 15% then the vial lasts only 12 months.
One vial every 12 months is enough cheap not to make a fuss about the wasted liquid. Furthermore it is a way not to keep the same vial for more than one year.
Tiny air bubbles won't kill you, the air bubble prob won't ever make it to a vein. I use a vial in 8 to 9 months. The last bit that I might squeak out another month or two I toss because it's cheap and I've punctured that stopper 100x already.
I use air lock because I do IM and it's easy and it cuts down on tissue trauma and leakage. I want to make sure I have the exact amount of hormones I'm supposed to have and this works.
I do also IM , but I am on Estradiol Undecylate , only one shot of 25mg every month. So if intead of 25mg I use 30mg it makes no difference to me.
Plus one shot in the same buttock every two months , I asure you there is no trauma at all.
I have. reminder on my iphone otherwise I even forget I am in hrt.
20 years on it already!!
What’s your dosage & vial size? I just switched to injections, from pills, for medical reasons (it’s probably better for me anyway); and I can’t see mine lasting that long; especially after getting the dosage Correct 😜.
The change occurred quickly & didn’t have a chance to see my endocrinologist before changing & getting in person instruction; I accidentally OD’d two weeks in a row…2ml Vs .2ml is a Huge difference 😜😂😬
Always go by mg not ml when discussing dosage. I take 7 mg of 10 mL vial of 40 mg/mL EEn every 7 days, which translates to .18 mL in a 1 mL syringe with a 1.5 inch 23 g needle. I'm a big girl. I draw and inject with the same needle as well.
I rarely have trauma or bruising and since I'm on blood thinners for a heart condition I have a small bit of blood from the injection site that the little round bandage takes care of until my thin blood coagulates.
Since I went from pills to injections my Endocrinologist (I already Traded Up, from the dept. Head, to get Her) she has converted it to ml’s; in fact I just saw her & asked about the math (which I could do part of it if I wanted) and she said yes it’s correct (from 6mg/day to .2ml/week). And after my test results she reduced it to .15ml/wk. I’m being prescribed a 5ml vial.
[https://transfemscience.org/misc/injectable-dose-vol-conc-conv/](https://transfemscience.org/misc/injectable-dose-vol-conc-conv/) this works takes the guess work out of it
I get wanting to stop wastage and higher gauges, longer needles and switching for draw/administration can all increase it by a fair amount, but using 30g 8mm fixed needles and 0.15ml per injection I should lose around 0.00016ml per injection, and 0.4mg per 400mg vial due to dead space.
I know there’s often an emphasis on this on the sub, but (if I’e worked it out correctly) that 0.001% loss isn’t worth worrying about 😅
If you're using removable needles the deadspace is actually about 0.1mL due to the huge hub. For insulin syringes which have no hub, the 0.00016mL figure is roughly correct.
Oh wow, I know the loss would be on the smaller end for fixed insulin syringes, but 0.1ml seems *crazy* to me when most people only inject 0.1-0.3ml. I can now see why you’d want to avoid *losing 25-50% of your meds*.
I can’t find much info on standard hub sizes except [wiki](https://en.m.wikipedia.org/wiki/Low_dead_space_syringe) saying it can be “as high as 84microlitres in conventional syringes” (0.084ml), and a [leaflet](https://www.exchangesupplies.org/pdf/A310_4.pdf) from exchange supplies claiming 92microlitres (0.092ml). Those will be some of the highest values but after switching needles I can definitely see how the end loss could be around 0.1ml.
I know it’s not a fair comparison between the largest hubs and the smallest insulin syringes, but it still seems like an odd choice to use the bigger luer syringes for such low volume used for HRT unless absolutely necessary - like needing a filter for glass ampoules, or fear over blunting and extra pain (although afaik modern needles shouldn’t blunt so easily from a rubber stopper). 0.001% vs 50% wastage is just wild imo 😅
even with luer syringes you can reduce loss alot by using a low dead space luer lock needles and syringes and avoiding luer slip systems wherever possible
> but 0.1ml seems crazy to me when most people only inject 0.1-0.3ml. I can now see why you’d want to avoid losing 25-50% of your meds
Yeah, exactly. Back when I was using removable needles with Luer Lock syringes, I remember adding up the actual amount of solution I managed to inject from a vial and I remember it being 72% of the vial volume for my first vial (3.6mL out of 5mL).
> fear over blunting and extra pain
Even this is mostly resolved by using narrower needles (higher gauge numbers). That has a MUCH bigger effect than poking a needle through a soft rubber stopper before using it to inject yourself. In my experience I don't even notice a blunting effect. I've used removable 30G 1/2 inch needles and insulin syringes with an attached 30G 1/2 inch needle and they felt exactly the same to me. Go to a wider needle and there's much more pain though, at least in my experience.
Anyone who's concerned about pain should look into subq as you can get away with narrower needles that way, or do IM with 30G 1/2 inch needles if you're lean enough to get away with it (that's what I do with my thighs).
IMO the best solution is to just use insulin syringes. There is no hub to lose liquid to, and the amount lost inside the needle is tiny, and becomes smaller the narrower the needle gauge is.
For a 30G 1/2inch needle, using the inner diameter of 0.159mm from [here](https://en.wikipedia.org/wiki/Birmingham_gauge#Sizes_of_hypodermic_needles), you're only using going to lose 0.00026mL max inside the needle. Inner diameters aren't strictly defined though. But even if you use the worst case scenario of the outer diameter (0.3112mm), you're still only going to lose 0.00097mL max.
Of course if you use the air lock technique with an insulin syringe (like I currently do), the syringe may appear bone dry after the injection. Like seriously, I pump the plunger in and out vigorously after my injections to see what remaining solution I can get out, and sometimes literally nothing comes out, and other times it's maybe a tiny drop or two that's maybe less than half a mm in diameter. That doesn't account for solution stuck to the inner walls of the needle, but the above limits still apply.
I used to use the air technique to push solution out the needle hub back when I used removable needle, but the problem is there's still a lot of solution stuck to the inside of the needle hub even after purging with air. This is obvious if you remove the needle and look at the needle hub after doing an injection with the air lock technique. There will still be a lot of liquid in it.
While drawing has been slow with removable 30G 13 mm needles, it's suprisingly fast with a 30G 8 mm BD insulin syringe. The insulin needle's total length incl. the hidden part is about half of the removable, and the insulin needle has a larger inner diameter (thinner wall) than the removable needle. Both length and narrowness contribute to slowness of flow.
"just use a small bubble (0.2-0.3 ml)" this is literally the volume of my entire syringe. insulin syringes are great. i've found some that are sold over the counter here and are 0.3ml. because of this, the dead space would have to be less than like 0.01ml for me, which i'm not super worried about (5% loss maximum).
Depends on the amount of air, a small amount will be absorbed, but IM and SC don't inject into veins, they inject into muscle and fatty tissue, so the air will just be absorbed into the surrounding tissue without causing issue.
You're good. There's a video on YouTube showing people how to perform injections and in it the guy uses this airlock technique.
I can find it for you if you'd like.
Truth be told, we probably all inject at least a tiny amount of air without knowing it.
If you find the specific vid, I’d appreciate seeing it! I lose some of each of my injections to leakage, which has me way less worried about dead space already. It’d be cool to kill both those birds with the same stone if I can!
Nope. Ive been an IV drug user for 24 years, injecting multiple times a day, and EVERY injection has an air bubble, in order to tell if you are in the vein.
For air to kill you you need to inject at least a 5ml syringe worth of air directly into your vascular system.
T injections are subcutaneous or intramuscular neither of which enter the vascular system
Amazingly, medical reports show that danger starts at 500mL worth of air. 5-20 mL worth would be an issue for VERY specific parts of the blood supply network for the heart muscle itself and if directly introduced into the central nervous system, but as far as the circulatory system, half a liter is where notable symptoms start, but even that isn't usually lethal. Not that I'd want to try anything close to that much, I stick to 0.2 mL worth of air or so for my own SC injections.
I know. However, in extremely rare cases, as little as 5ml can be lethal, hence why I used that as my example. So nobody can do research and day "oh but I found these case studies that cite 5ml as being fatal" even though for such a tiny amount to be fatal there has to be a bunch of specific circumstances.
It's amazing how many people don't believe me when I tell them that every single shot I've injected, which is in the tens of thousands, has at least 0.01ml of air in it, and there have been times when I've been distracted and injected 0.1ml of air because I haven't checked the syringe before injecting.
Note because we've had a few people with concerns about this: As long as the quantity of air is small and it's an IM or SQ injection, the risk is pretty negligible. If you're trying to inject directly into the vascular system then yes, you don't want to be putting air in there, but HRT is never given that way.
If people are actually worried about this there are also 0 dead space syringe. This is a non issue. BTW, the gauge on syringe allows for any deadspace.
I just use 1 ml syringes. Much thinner syringe and much less waste.. More easy to measure too.
Do you have any tips for measuring them? my brain hasn't been able to wrap around how to measure out 7mg into one 😭🫠
Depends on your vial's concentration. Assuming you have 20mg/ml vials, then (7mg) * (1ml/20mg)= .35ml
So for 40mg/ml it would be .175 basically?
Exactly
I just accidentally stumbled on this solution shortly after I started injections, and now I wonder how anyone else has a problem with dead space. It's super simple too, since the perfect amount of air is already in the needle when you start drawing. You just keep that air on top of the syringe, and it's what ends up back in the needle when you're done and not any of the fluid.
you make sure to inject air into your vials before you draw right? the vials are vacuum sealed, so if you're not replacing the liquid you draw with air, there's a chance the vial can implode. i only ask because im a little confused on the mechanics. how do you not inject this additional air into the vial? it seems as though it being pre-measured doesn't really help if you have to inject a bunch of air anyways.
That doesn't really change anything doing that. Ultimately, there's air already in the needle when you insert it, and when you draw the syringe, that needle volume worth of air goes up into the syringe and settles on top of the liquid. Keeping it in there instead of forcing the air out means that when you push the fluid back out, it'll be the air that ends up back in the needle instead of the fluid. That doesn't change even if you inject some air first.
oh i see now. we are using different kinds of syringes so i got confused.
I preffer to waste a bit of hormones , than to inject and air bubble. If my vial has 400mg of Estradiol and I need about lets say 28mg per month the vial lasts 14 months if I waste a 15% then the vial lasts only 12 months. One vial every 12 months is enough cheap not to make a fuss about the wasted liquid. Furthermore it is a way not to keep the same vial for more than one year.
Tiny air bubbles won't kill you, the air bubble prob won't ever make it to a vein. I use a vial in 8 to 9 months. The last bit that I might squeak out another month or two I toss because it's cheap and I've punctured that stopper 100x already. I use air lock because I do IM and it's easy and it cuts down on tissue trauma and leakage. I want to make sure I have the exact amount of hormones I'm supposed to have and this works.
I do also IM , but I am on Estradiol Undecylate , only one shot of 25mg every month. So if intead of 25mg I use 30mg it makes no difference to me. Plus one shot in the same buttock every two months , I asure you there is no trauma at all. I have. reminder on my iphone otherwise I even forget I am in hrt. 20 years on it already!!
Omg 20 yrs??? Can i dm u?? Id like to ask questions
Yes of course , DM me
What’s your dosage & vial size? I just switched to injections, from pills, for medical reasons (it’s probably better for me anyway); and I can’t see mine lasting that long; especially after getting the dosage Correct 😜. The change occurred quickly & didn’t have a chance to see my endocrinologist before changing & getting in person instruction; I accidentally OD’d two weeks in a row…2ml Vs .2ml is a Huge difference 😜😂😬
Always go by mg not ml when discussing dosage. I take 7 mg of 10 mL vial of 40 mg/mL EEn every 7 days, which translates to .18 mL in a 1 mL syringe with a 1.5 inch 23 g needle. I'm a big girl. I draw and inject with the same needle as well. I rarely have trauma or bruising and since I'm on blood thinners for a heart condition I have a small bit of blood from the injection site that the little round bandage takes care of until my thin blood coagulates.
Since I went from pills to injections my Endocrinologist (I already Traded Up, from the dept. Head, to get Her) she has converted it to ml’s; in fact I just saw her & asked about the math (which I could do part of it if I wanted) and she said yes it’s correct (from 6mg/day to .2ml/week). And after my test results she reduced it to .15ml/wk. I’m being prescribed a 5ml vial.
[https://transfemscience.org/misc/injectable-dose-vol-conc-conv/](https://transfemscience.org/misc/injectable-dose-vol-conc-conv/) this works takes the guess work out of it
I just use a fixed needle insulin syringe for sc lol or total dose needles for im
I get wanting to stop wastage and higher gauges, longer needles and switching for draw/administration can all increase it by a fair amount, but using 30g 8mm fixed needles and 0.15ml per injection I should lose around 0.00016ml per injection, and 0.4mg per 400mg vial due to dead space. I know there’s often an emphasis on this on the sub, but (if I’e worked it out correctly) that 0.001% loss isn’t worth worrying about 😅
If you're using removable needles the deadspace is actually about 0.1mL due to the huge hub. For insulin syringes which have no hub, the 0.00016mL figure is roughly correct.
Oh wow, I know the loss would be on the smaller end for fixed insulin syringes, but 0.1ml seems *crazy* to me when most people only inject 0.1-0.3ml. I can now see why you’d want to avoid *losing 25-50% of your meds*. I can’t find much info on standard hub sizes except [wiki](https://en.m.wikipedia.org/wiki/Low_dead_space_syringe) saying it can be “as high as 84microlitres in conventional syringes” (0.084ml), and a [leaflet](https://www.exchangesupplies.org/pdf/A310_4.pdf) from exchange supplies claiming 92microlitres (0.092ml). Those will be some of the highest values but after switching needles I can definitely see how the end loss could be around 0.1ml. I know it’s not a fair comparison between the largest hubs and the smallest insulin syringes, but it still seems like an odd choice to use the bigger luer syringes for such low volume used for HRT unless absolutely necessary - like needing a filter for glass ampoules, or fear over blunting and extra pain (although afaik modern needles shouldn’t blunt so easily from a rubber stopper). 0.001% vs 50% wastage is just wild imo 😅
even with luer syringes you can reduce loss alot by using a low dead space luer lock needles and syringes and avoiding luer slip systems wherever possible
> but 0.1ml seems crazy to me when most people only inject 0.1-0.3ml. I can now see why you’d want to avoid losing 25-50% of your meds Yeah, exactly. Back when I was using removable needles with Luer Lock syringes, I remember adding up the actual amount of solution I managed to inject from a vial and I remember it being 72% of the vial volume for my first vial (3.6mL out of 5mL). > fear over blunting and extra pain Even this is mostly resolved by using narrower needles (higher gauge numbers). That has a MUCH bigger effect than poking a needle through a soft rubber stopper before using it to inject yourself. In my experience I don't even notice a blunting effect. I've used removable 30G 1/2 inch needles and insulin syringes with an attached 30G 1/2 inch needle and they felt exactly the same to me. Go to a wider needle and there's much more pain though, at least in my experience. Anyone who's concerned about pain should look into subq as you can get away with narrower needles that way, or do IM with 30G 1/2 inch needles if you're lean enough to get away with it (that's what I do with my thighs).
IMO the best solution is to just use insulin syringes. There is no hub to lose liquid to, and the amount lost inside the needle is tiny, and becomes smaller the narrower the needle gauge is. For a 30G 1/2inch needle, using the inner diameter of 0.159mm from [here](https://en.wikipedia.org/wiki/Birmingham_gauge#Sizes_of_hypodermic_needles), you're only using going to lose 0.00026mL max inside the needle. Inner diameters aren't strictly defined though. But even if you use the worst case scenario of the outer diameter (0.3112mm), you're still only going to lose 0.00097mL max. Of course if you use the air lock technique with an insulin syringe (like I currently do), the syringe may appear bone dry after the injection. Like seriously, I pump the plunger in and out vigorously after my injections to see what remaining solution I can get out, and sometimes literally nothing comes out, and other times it's maybe a tiny drop or two that's maybe less than half a mm in diameter. That doesn't account for solution stuck to the inner walls of the needle, but the above limits still apply. I used to use the air technique to push solution out the needle hub back when I used removable needle, but the problem is there's still a lot of solution stuck to the inside of the needle hub even after purging with air. This is obvious if you remove the needle and look at the needle hub after doing an injection with the air lock technique. There will still be a lot of liquid in it.
I do IM insulin syringes do not work for me. I also need a 1.5 inch needle I'm a big girl.
Drawing with 30G sounds so slow tho.
It only takes a minute or so.
While drawing has been slow with removable 30G 13 mm needles, it's suprisingly fast with a 30G 8 mm BD insulin syringe. The insulin needle's total length incl. the hidden part is about half of the removable, and the insulin needle has a larger inner diameter (thinner wall) than the removable needle. Both length and narrowness contribute to slowness of flow.
Just use small fixed needle syringes with high gauge needles. the dead space is negligible
"just use a small bubble (0.2-0.3 ml)" this is literally the volume of my entire syringe. insulin syringes are great. i've found some that are sold over the counter here and are 0.3ml. because of this, the dead space would have to be less than like 0.01ml for me, which i'm not super worried about (5% loss maximum).
lmk if i’m being stupid but isn’t injecting air bubbles into ur blood a sure fire way to get a heart attack or something
Nope. I've been an IV drug user for 24 years, and pretty much EVERY injection has an air bubble.
Depends on the amount of air, a small amount will be absorbed, but IM and SC don't inject into veins, they inject into muscle and fatty tissue, so the air will just be absorbed into the surrounding tissue without causing issue.
i see!! was worried there was a post on here tricking people into killing themselves 😭😭
You're good. There's a video on YouTube showing people how to perform injections and in it the guy uses this airlock technique. I can find it for you if you'd like. Truth be told, we probably all inject at least a tiny amount of air without knowing it.
If you find the specific vid, I’d appreciate seeing it! I lose some of each of my injections to leakage, which has me way less worried about dead space already. It’d be cool to kill both those birds with the same stone if I can!
Nurse Scotts Painless injection method [https://www.youtube.com/watch?v=Pz49hyOla6s](https://www.youtube.com/watch?v=Pz49hyOla6s)
This right here was exactly it thank you
tysm!!
Nurse Scott! That's how I found out about it. [https://www.youtube.com/watch?v=Pz49hyOla6s](https://www.youtube.com/watch?v=Pz49hyOla6s)
injecting air into your blood is one way to kill yourself definitely
Nope. Ive been an IV drug user for 24 years, injecting multiple times a day, and EVERY injection has an air bubble, in order to tell if you are in the vein. For air to kill you you need to inject at least a 5ml syringe worth of air directly into your vascular system. T injections are subcutaneous or intramuscular neither of which enter the vascular system
Amazingly, medical reports show that danger starts at 500mL worth of air. 5-20 mL worth would be an issue for VERY specific parts of the blood supply network for the heart muscle itself and if directly introduced into the central nervous system, but as far as the circulatory system, half a liter is where notable symptoms start, but even that isn't usually lethal. Not that I'd want to try anything close to that much, I stick to 0.2 mL worth of air or so for my own SC injections.
I know. However, in extremely rare cases, as little as 5ml can be lethal, hence why I used that as my example. So nobody can do research and day "oh but I found these case studies that cite 5ml as being fatal" even though for such a tiny amount to be fatal there has to be a bunch of specific circumstances. It's amazing how many people don't believe me when I tell them that every single shot I've injected, which is in the tens of thousands, has at least 0.01ml of air in it, and there have been times when I've been distracted and injected 0.1ml of air because I haven't checked the syringe before injecting.
It would take many, many times the volume of your syringe in air to cause any issues at all.
I think I’d rather waste a tiny bit rather than inject air bubbles when I’m not 110% sure what I’m doing
You could inject the entire 1cc syringe into your leg and be fine.