Microdoses, an explaination.

Microdosing.....

Some cats just don't need as much insulin. Insulin needs can decrease with the elimination of dry food from the diet, improved absorption of insulin, the P starting to produce insulin,.....who knows why all the time, but sometimes very small doses of insulin are needed.

You will need u100 needles with half unit markings, adjustments at these small doses are 0.1u increments. Shots are still given on a 12/12 basis, but sometimes when a cat is going into remission you will get long cycles or skip a shot. Starting out though, you should start your injections at a time that will work for your schedule both am and pm. Drawing smaller doses takes a different technique. Air bubbles in a syringe are always a problem, but an air bubble in 0.1u can be over half the dose. Draw excess insulin into the syringe and knock the bubbles to the top and push them out. Push the plunger close to where it needs be, but leave the dose a bit larger then you need. If you try to push the plunger to the correct spot you will be going back and forth forever, instead get it close and then rotate the plunger clockwise like you are screwing it in. This pushes insulin out one drop at a time and makes it much easier.


If you have a cat that is staying around 200 without insulin, start with 0.1u on a day when you are home to monitor how it goes, run a mini curve and see what happens. Your expectations for this curve would be the same as when you were on larger doses, numbers should go down midcycle and it'd be great to see a high green or 100. Keep you ss updated and have someone review the curve to see how the dose looked and if it should be held or increased. Once you know how the small dose is working you can decide on your no-shoot number.

Cathy

 

This is great, Cathy. Thanks!

 

This helps tremendously, thank you. To make sure I have the right needles since your .1 looks like a 1 on my needle, it has an orange cap, says 1/2 mL, U-100 Insulin, Single Use Only. There are large numbers 5, 10, 15, 20 etc. with lines for in-between. The reason I want to check is because I don't see any .1, just regular numbers.

Any suggestions on a good no shoot number? The last time Chong was in remission (6 months) she stayed at about 100-110. The vet at the time had me giving 1 unit U-40 when Chong's BG was in the 60s. Now that I know more, it's a wonder she survived the vet!

Thanks.

Barb & Chong

 

Sounds like those needles only have whole unit markings.the half units would be on a separate scale next to the whole units, typically to the right.so if you don't have two sets of lines then they are not the ones you'll need.

Right now I wouldn't shoot below 180, and you'll want a couple of tests to confirm that the 180 isn't falling. I would never shoot below 150even after you've collected some data.

 

Let me find a picture for you...

The caps are orange? That means they are U100s...red caps are U40s
The smallest measurement that would be numbered would be whole unit markings, with the half unit marks on the opposite side of the line that runs from the needle to the plunger. That would be the .5 marks. I don't believe anyone makes a syringe with numbered "less than whole unit" hash marks.

I you were shooting .1 of Prozinc using that U100 syringe, you would draw the insulin past the line and then gently squeeze the plunger until you were half way between the ".5" line and the zero line, which would be .25u (U40 dose times 2.5)



Carl

 

Hi,
I'll email the vet and ask for more details on the experiment.

Can someone just tell me what I gave Chong in U 40 language?

U 100 Syringe - there are no other lines on the syringe although the bag and the needle say it is 0.5mL volume. It has orange cap. It looks like the one on the right on Carl's picture.
__
_ I gave her to this line.
_
_
_
_5
_
_
_
_
_10

Thank you.

 

You gave 1 unit on the U100 syringe, which is equal to ".4" units of PZI. 4/10ths of a unit.

The rest of the lingo on the box means this:

.5ml volume - that means that the whole syringe is capable of holding 1/2 of a milliliter of liquid. There are 50 units in a total .5l volume syringe. The scale probably goes up to 30? With room left over before the plunger would pull clear of the tube? Theoretically, you could fit another 20 units in there. A human might get that much insulin in a shot, where a cat never would, but the syringes were intended for use with human insulin on humans.

some syringes also have 1/2" or 5/16" somewhere in their description. That is the length of the steel needle on them.

sometimes it says .5cc instead of .5ml. Those are the same thing. One cubic centimeter is the same as one milliliter in terms of volume. They also make syringes that hold .3cc or ml. Most U40s are that size. It just means the capacity of the syringe is less, it will only hold 3/10ths of a cc/ml instead of 1/2.

The real difference between the two syringe types is the insulin that is supposed to be used in them. U100 insulins, like lantus for instance, are 2 and a half times as potent as prozinc (a U40 insulin). Lantus has "100 parts per ml" while Prozinc only has "40 parts per ml". So when you put Prozinc in a syringe intended for use with a more potent insulin, it "looks" like you are shooting more, but you aren't actually doing that. The scale is just smaller, so the number is higher. But it's the same volume of liquid.

Did that help, or just make it worse? ;-)

Carl

 

OMG. Thank you. Got the gist. So glad I didn't OD her again!

 

The big advantage that Prozinc/PZI users have as far as syringes go is that we can use U100 syringes when we get to the point where the dose is too small to measure with any degree of accuracy with "our" syringes.
When people using lantus or levemir get to the mini-micro dose stage, they don't have another syringe choice that makes it easier to see or measure. So, we're fortunate in that way.

Carl