Insulin syringe

Okay I know, I know…it’s me again! I have a question. If you are drawing your insulin dosage and you are supposed to inject 1.2 units, how do you draw that? I have a syringe that is 50units and it is 1/2cc. I don’t have half marks, it just starts off 1,2,3,4, and then the number 5 and then the lines for 6789 then the number 10 and so on.

Well, you can take a guess, but mostly you are just out of luck. You can get 1/3 cc syringes with half marks, but that still won’t do tenths. I just round it off, so 1.2 is 1 unit, 1.6 is 2 units. For those that are particularly insulin sensitive, this is a real problem. I am not particular sensitive, so I never take 1 or 2 units, maybe 5, not 1.

Is that helpful? Probably not. Sorry.

You can’t. That’s the drawback to MDI vs pumps. Most syringes only list whole units. There are some that do 1/2 units and I’m sure someone will list the names of those. If you are very insulin sensitive it might pay to get one. For me, for example my hardest meal to bolus for on MDI was dinner because my I:C ratio was 1:18. When I was on MDI I found it worked best if I rounded up. So if my I:C was 1:8 and I ate 22 carbs I would bolus 3 units. From experience I found this to work better for me than to round down. But it is hardly an exact science. I love my pump because I can give boluses in increments of .025. But I did manage to have decent A1C’s for two years on MDIs. If you find you are always low if you round up you might want to either round down or else change your I:C ratio. For me it worked best if I was consistent - that is always rounded up. The only time I deviated from this was If I was on the low side before my meal I would round down. Bottom line is what works best for your numbers.

No that is very helpful! Thank you!

okay zoe I will play with this. You guys rock as always!

I think I could only manage maybe .5. Like some others I go by whole numbers, and when in doubt I go to the lessor of the 2.

I was told by my CDE - back when I was using syringe - now on pump - round down if you plan to be active. Roud up if you plan to veg out and be a couch potato …

I think there’s pretty small syringes available that will mark off the increments? One of my friends had Type G and gave me her leftover syringes when she was done. I always liked the bigger ones so they were a bit dainty for my tastes but they had some pretty fine gradations. I probably still have some in a box around here. I always just blew it off and adjusted doses by like 5 U chunks but, when I got my pump, I was sort of astounded to learn that .2U/ hour can make a big difference in stuff like basal rates?

You have to have a good eye for distance measuring. The profession from which I am retired (trauma radiography), I had to be precise with measurements. I use 30 unit syringes, with half unit markings. So I do dose as precisely as possible, and for me, it works.

Taking bsc’s formula, if I only needed 1.6 units, I would not round up to 2 units. That can bring about hypos, and caused me many of them, when I happened to go to one particular endork. We eventually fired each other - he didn’t like me setting my own doses, among other issues we had. For that 1.6 units, I would do 1.5. Even with one unit marks, you can / should be able, to visualize where halfway is.

On the side of caution, it is always best to round down, especially for we hypo-unaware folks.

Be careful and good luck, if you try to do precise dosing. Oh yeah, BD makes the 30 unit syringes with / without the half unit markings.


That is a good point that even though there aren’t marks, you can set the plunger halfway between the ticks. But your post also brings up another point which I did not mention earlier. You apparently use small doses, so even half unit increments can result in crude levels of control. It is possible to dilute insulin. I’ll not describe the process, but for those veterans who still depend on a trusty syringe and have a small TDD it is an option.