First injection and concern with dead space in syringe

Hello guys,

I'm new here and have been soaking up as much info as I can.
I literally just finished my first injection using a 1mL tuberculin syringe with a 21g to draw and a 25g to inject into my quad. Surprisingly painless. I did notice something that I couldn't seem to find any info on.
I pulled back to the .5 line and pulled the needle out of the vial. Once out, I pulled back more on the plunger to get any remaining oil out and noticed there was really about .55 of oil (between .5 and .6) in the syringe.

I also noticed the "0" or "starting line" at the tip of the syringe. I don't know if I measure from this line or to include the oil thats left in the needle itself and the very tip of the syringe. I'm not sure if I am explaining this clear. Please pardon my ignorance as I am still new and learning. I just don't want to be injecting to much or too little and not sure how to get the most accurate dose.

Thanks for any help. Much appreciated.

There's no reason to stab yourself with a 25g harpoon, we all use the 29g 1/2", and you won't have any dead space/waste issues with this syringe, the U100 insulin.

I wouldn't worry too much about it, if you do it the same every time. The issue you may have, will you run short before it's time to reorder. I use an easy touch insulin syringe, for HCG and testosterone.

Vince Carter said:

There's no reason to stab yourself with a 25g harpoon, we all use the 29g 1/2", and you won't have any dead space/waste issues with this syringe, the U100 insulin.

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LOL c'mon man. Harpoon lol. They said that that about the 21g and the 23g, now the 25g? I use the syringe you're using for hgh every morning and that hurts more than the 25g in the thigh.

Vince said:

I wouldn't worry too much about it, if you do it the same every time. The issue you may have, will you run short before it's time to reorder. I use an easy touch insulin syringe, for HCG and testosterone.

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Thanks, this was my next question. I heard the pharmaceutical companies overfill the vials to compensate for this. Any truth to this?

ZoomyR6 said:

LOL c'mon man. Harpoon lol. They said that that about the 21g and the 23g, now the 25g? I use the syringe you're using for hgh every morning and that hurts more than the 25g in the thigh.

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FNG with new guy questions comes back with some kinda answer like he knows things LOL

The only thing I know is what I stated above. That and using trt SubQ has a new following and using an older method is wrong...
That's the extent of my knowledge.

ZoomyR6 said:

Thanks, this was my next question. I heard the pharmaceutical companies overfill the vials to compensate for this. Any truth to this?

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Some compounding pharmacies do overfill their vial, not all.

Empower Pharmacy seems to overfill Test cyp.

ZoomyR6 said:

LOL c'mon man. Harpoon lol. They said that that about the 21g and the 23g, now the 25g? I use the syringe you're using for hgh every morning and that hurts more than the 25g in the thigh.



Thanks, this was my next question. I heard the pharmaceutical companies overfill the vials to compensate for this. Any truth to this?

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Personal preference. 25g is hardly a harpoon. Good for both uptake and intramuscular as Nelson has noted. As I see it the main advantage to using fixed fine insulin needles is no waste. Low dead space Luer lok is available making the use of insulin syringes much less advantageous. Try both IM and sub.

Vince said:

Some compounding pharmacies do overfill their vial, not all.

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Ah so it's possible to run out actually run out a tad early. Thanks.

Pranayama said:

Empower Pharmacy seems to overfill Test cyp.

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Thank you

Re-Ride said:

Personal preference. 25g is hardly a harpoon. Good for both uptake and intramuscular as Nelson has noted. As I see it the main advantage to using fixed fine insulin needles is no waste. Low dead space Luer lok is available making the use of insulin syringes much less advantageous. Try both IM and sub.

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Thank you for the response. My order of syringes and needles just came yesterday so I will be a while to re-order. Perhaps i'll give subQ a shot (pun intended) with the 29g 1/2in slin syringes I have. I just want to get my blood pulled on IM before switching.



Speaking of blood, I have been reading conflicting info on when to get it tested. I was going to do it at 5 weeks but how many days after my last shot? I read 3-4 days when its at peak then I read 7 days when it's at its lowest. Any input?

Zoomy, you would want to draw at the trough to see how your levels are running between injections.
Drawing at other times can give you a picture of other things if that info is needed (peak).

ZoomyR6 said:

Ah so it's possible to run out actually run out a tad early. Thanks.


Thank you



Thank you for the response. My order of syringes and needles just came yesterday so I will be a while to re-order. Perhaps i'll give subQ a shot (pun intended) with the 29g 1/2in slin syringes I have. I just want to get my blood pulled on IM before switching.



Speaking of blood, I have been reading conflicting info on when to get it tested. I was going to do it at 5 weeks but how many days after my last shot? I read 3-4 days when its at peak then I read 7 days when it's at its lowest. Any input?

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You want to draw, as JV63 noted, at your thought. That means just PRIOR to an injection.

Thanks guys. What is a good reference range to go by since it will be at its lowest? Is there any type of formula that can calculate what it is during peak?