@Eric Thanks @Eric! I didn’t know they made 1/2" pen needles. I have to stop by the pharmacy tonight and I’ll see if they carry them.
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@docslotnick
This is what you want. BD makes good stuff.
Available on Amazon:
https://www.amazon.com/Ultra-Fine-Pen-Needles-Count/dp/B007XNK8ZO/ref=sr_1_1_a_it?ie=UTF8&qid=1504281817&sr=8-1&keywords=BD+1%2F2+inch+needle
@TiaG,
You can get them from Mountainside Medical.
Here is the link for one brand, or you can go their main page and do a search for product number AL-SV1020:
I have used the Hospira brand before, but they are currently on backorder:
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The little bit of research I’ve found on the subject has shown that even in skilled hands neither pens or syringes accurately deliver doses of 1u or less, but that pens come closer.
Good points on the small size… you are certainly able to carry more units of insulin in a vial than in a pen–
My theory on the 'leakage" with a pen but not a syringe is that when you pull a pen out from your skin you’re drawing a tiny vacuum into the pen which sucks a little bit out of the pen as you withdraw it… this same vacuum would occur in a syringe too, but of course they’re empty after use so there’s no droplets drawn out… just my theory… but I don’t think the droplets you see on a pen tip needle after use indicate that some insulin was not delivered that should have been…
Would be interesting test to do… use s syringe but don’t inject all the units, only half of what’s in the syringe or so— see if you get any leakage
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Just wanted to throw this out as a suggestion to people who see their pens “leak”…
If you prime your pen while pointing the needle up toward the ceiling, the priming insulin runs down to the base of the needle (where the needle connects to the pen). If you then point the pen downward when you inject, and then pull it out, the priming insulin that was sitting at the base of the needle has now trickled onto the injection site and you are seeing that insulin and think it was a leak, but it wasn’t! It was the priming insulin, not a leak…
Make sense? I know that was a confusing paragraph. If it doesn’t make sense, lemme know and I will try again.
Short version - when priming, point your needle toward the floor.
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I don’t think this is the problem. I always prime downwards but often see a little drip on the pen needle.
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It may not be cause of every leak people are seeing. But if you ever prime with the pen “up” and then immediately inject with the pen “down”, you are almost certainly guaranteed to see some of that priming insulin on your skin.
So I think “prime down” is a good habit for everyone to practice, just to eliminate it as a possible cause.
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When I was diagnosed, I was told to prime upwards to get rid of air bubbles.
I just did a very quick proof-of-concept of my thought that the primed insulin can appear as a leak. This is a very easy test everyone can do themselves. You don’t need to actually inject any insulin to see this.
I primed 2 units with the needle pointing up. Of course this caused the insulin to drip down all over the base.
I then inverted the pen and injected downward, into my leg. But, I did not actually inject anything. I just pushed the needle into my skin. I left it there for a few seconds just like they tell you to do, and then removed it.
Sure enough there was a big drop of insulin at the injection site. It looked just as if it had leaked out of my leg.
Obviously nothing had actually leaked out of my leg, because I didn’t inject anything.
But it sure looked like it had leaked out of my leg…
This is a very easy thing for people to test out themselves.
What if you prime downwards? I always prime downwards into my hand so I can feel if insulin comes out. I still get insulin either leaking from the injection site or dripping from the end of the pen when I remove it.
I am sure you can still get leaks from pens. As I said to Michel:
So this isn’t a suggestion on how to get rid of the leak. But I was simply suggesting that removing the possibility of insulin dripping off the base would at least eliminate that single issue.
Then if you still see a leak, you know it is something else.
I do the same thing. When using a pen at night in the dark, I always prime onto the back of my hand to feel it.
And-- you drew a vacuum into the pen when you withdrew it from your flesh, sucking insulin out of the pen in my theory… which I think holds up to scrutiny pretty well… try it out-- prime the pen pointing down then stab yourself with it and see when you pull it out if and insulin is working is dribbling out…
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In order for insulin to be drawn out via a vacuum, the plunger would need to move. The volume of liquids can not be changed. Liquid can neither be expanded or compressed. The pen cartridge is a solid shape, made of hard plastic. It’s shape does not change.
So if your theory is true, the vacuum would need to be strong enough to move the pen plunger.
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Technically you’re correct but on the scale of moving a tiny droplet through the needle— I think it’s possible. Can also be evidenced by changes in barometric pressure causing insulin to be much more eager to shoot out of the vial sometimes than others… without the plunger moving
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You may be right. I just tried it—primed the pen, then injected twice but without dialing up the plunger—and both times my skin was wet with a drop or two of insulin after pulling it out.
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Imagine you have a sealed container full of liquid with a drinking straw in it, airtight except through the straw and not flexible (comparable to the vial without the plunger moving)
If you sucked on the straw do you believe you’d not be able to vacuum out a single droplet of liquid? I think you could-- I think it’d just get very difficult to get more very quickly
ETA Maybe that’s a bad example-- I just tried to suck bong water with my hand over the bowl part and it didn’t work.
Kidding… kinda bad example though
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I am not experienced on the fluid dynamics of a bong. But I do know that liquid can’t evacuate a space unless either air or a different liquid replaces that space.
I can try an experiment. If I neither prime the pen, nor inject with the pen, I only insert the needle, wait a few seconds, and remove the pen. And then see if anything leaks out. Is that the experiment you would propose?
100 times maybe? I can post a picture of my bloodied thigh.
Nah to make it accurate prime the pen 1 unit between each poke… pointing in such a direction to ensure it doesn’t flow back onto the device
But yes I am suggesting that a primed pen will draw out a bit of insulin each time it is withdrawn from flesh without the plunger moving, many if not most of the times enough to be visible and noticeable
I could be wrong but that’s my hypothesis
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Alright, fair enough. I can try it that way. After I find my tequila bottle.
Can’t just use the same needle til it clogs up with flesh either