Syringe size mistake overdose?

Discussion in 'Welcome to the Group - Post an Introduction Here' started by Terri Monroe, Jun 28, 2015.

  1. Terri Monroe

    Terri Monroe New Member

    Joined:
    Jun 28, 2015
    Hi Everyone!

    So, my name is Terri, and I'm Jinx's mom. He just turned 17 last month and was diagnosed 6 months ago. This post will be long, but PLEASE bear with me. I need some advice!

    He has had his ups and downs, but nothing as serious as his severe hypo episode about weeks ago. I came home from work to find him not moving, breathing, but VERY cold and stiffening up. I, of course, freaked out, rubbed some Karo syrup on his gums and rushed him to the Vet. His glucose level was at 36. Any longer and he wouldn't have made it. Apparently he didn't eat enough before I left for work.

    Fast forward to a few days ago when I stopped in to get another pack of syringes (Vetsulin u-40, pack of 100 w/disposal container). When I went to give him his insulin and opened the package, I noticed a much smaller syringe size than before, ( 3/10 vs 1/2 cc size) so i looked at the previous container as I was still using it for disposal. The OLD container said u-100, and the NEW one is u-40, which is what he SHOULD be on.

    I immediately called the Vet to question whether or not he was getting overdosed, as the amount of insulin in the syringe just didn't look the same between the two different size syringes. She asked if I could bring the container in, as they don't usually get u-100 size. I did, and they concluded that the manufacturer must have made a mistake in their supplies. When I asked again if he could have been getting too much, she said no, he was getting the same or even less. Huh???? That doesn't make sense to me AT ALL. Since being on the u-40, 3/10 size syringes, he is doing MUCH better.

    His major hypo episode, and a subsequent one, along with the damage that it may or may not have caused, (he now occasionally forgoes the litter box to poop), not to mention the fact that he almost DIED, the expenses at the Vet to save him, I'm super confused on this. From what I read, and I'll include it here, says that there could be dire consequences if the two syringes are interchanged. (This, from the ADW Diabetes site).

    ***Remember to always check the concentration of the insulin and match the syringe to that insulin. Vetsulin is U-40, meaning that there are 40 units of insulin per cubic centimeter or milliliter. Many insulins are U-100, meaning that there are 100 units of insulin per cc or ml. Using U-100 syringes with a U-40 insulin could result in overdosing your pet. Although there are conversion tables that can be found on the internet, I strongly advise against using a U-100 syringe with a U-40 product. One little math error can have dire consequences. Use a syringe that matches the insulin concentration.***
    This was written by a Veterinarian that specializes in Feline Diabetes.

    Can anyone help me clear up my confusion, please? Thank you SO MUCH!!!!

     
  2. Larry and Kitties

    Larry and Kitties Well-Known Member

    Joined:
    Dec 28, 2009
    Using a U100 syringe with a U40 insulin will results in a reduced does of insulin if your draw each syringe up to the same unit marking. The dose with reduce by over a half,, reduced by 2.5 times.
    Your situation was that yo changed from a U100 syringe to a U40 syringe and drew up the insulin to the same unit marking. That results in a does 2 1/5 times what was intended.

    Yes, it is best to use a syringe that matches the insulin to help avoid confusion
     
  3. Sue and Oliver (GA)

    Sue and Oliver (GA) Well-Known Member

    Joined:
    Dec 28, 2009
    http://www.felinediabetes.com/insulin-conversions.htm
    It is possible to use U100 syringes with U40 insulin. Many ProZinc users here do it because you can dose tiny amounts more easily.

    But yes, if you do so, you must use the conversion chart. Looking at it, you can see that you may have been giving less insulin than you thought, not more. So your vet was right in that case, but it is definitely not the same amount. For instance, if you had been giving 2 units of your insulin in a U100 syringe, the dose was actually only .8. So he was getting less insulin than you thought. If he hypoed, you might be careful that he isn't now getting too much.
     
  4. Mitzelplik's Mom

    Mitzelplik's Mom Member

    Joined:
    Jan 24, 2015
    Hi Terri,
    Yes, it is confusing! Here's the conversion chart to illustrate what Larry is saying:
    http://www.felinediabetes.com/insulin-conversions.htm
    If you draw u-40 insulin to the 1 unit mark on U-100 syringe, it's actually only 0.4 units of the U-40 insulin. So now that you're using the correct U-40 syringe with your U-40 insulin, Jinx is getting more insulin than he was before. Are you able to test Jinx at home? That's what most people here do ignored to keep our cats safe.
     
  5. Terri Monroe

    Terri Monroe New Member

    Joined:
    Jun 28, 2015
     
  6. Brashworks

    Brashworks Member

    Joined:
    Jun 21, 2015
    Hi Terri, welcome and sorry you had to join here under those circumstances. I'm glad to hear Jinx is doing better!

    Could you clarify something, as I don't want to guess.

    When Jinx had his hypo, are you saying you were using the u100 syringes with the Caninsulin? Per the chart Mitzelplik's Mom linked to, if Jinx was taking, say 2.0u Caninsulin, you would need to draw 5.0u on a 100u syringe to make an equivalent dose. Mathematically speaking, changing to a 100u syringe with a 40u insulin wouldn't result in an "overdosing" but certainly an incorrect dose, and he was getting 2.5 times less than he would have been prescribed.

    So, the confusing part is, of course, if he was getting less, how is it possible he went hypo and how scary it must be having gone through that if he is now actually getting more?

    I have Genghis on Caninsulin right now, too, and understand it is 30% fast-acting and 70% long-acting. BJM suggested I feed ½ hour before she gets her dose for that reason, and again an hour to 2 hours after - this has worked very well for us. Given you have to leave for work the second feed doesn't sound practical but could you maybe feed Jinx before you inject? Do you test right before you inject also? For me it has taken at least some of the worry out of it.

    I'm not comfortable suggesting any particular course of action but for my own situation, if my girl didn't eat before her injection and I had to go to work, I probably wouldn't inject her at all - better she be high for the day than go hypo. I stress, this may not be the right course for Jinx, but a thought.
     
  7. Terri Monroe

    Terri Monroe New Member

    Joined:
    Jun 28, 2015
    Hi all. Thank you for the input, but I'm still a bit confused. The article that I posted from a Feline Diabetes Veterinarian specifically states that using a u-100 syringe would result in overdosing if used with u-40 insulin. I forwarded the article to my Vet, and she replied back that she feels now she was wrong in her thinking, and that Jinx was being overdosed. She agrees with the article, and has since done more research.

    I just received a home monitor, and he is doing so much better using the u-40 syringes, with NO hypo episodes, even if he doesn't eat much, which was a real problem for us.

    Thank you all again, I really do appreciate it! =^^=
     
  8. Terri Monroe

    Terri Monroe New Member

    Joined:
    Jun 28, 2015
     
  9. Terri Monroe

    Terri Monroe New Member

    Joined:
    Jun 28, 2015
    Hi Brashworks! Jinx is on Vetsulin. As for him not eating enough that day, i wrongly assumed he ate enough (never again!) as he was eating when I left, but apparently must have stopped as soon as I was gone. :( When he had his hypo episode, I was using the u-100 syringes at a dosage of 2 units.
     
  10. Brashworks

    Brashworks Member

    Joined:
    Jun 21, 2015
    Terri, I'm so glad Jinx is doing better and I think after this you can rest assured he was not previously overdosed. I can't imagine what you've been through. Maybe wait to see if anyone more experienced can comment on the food issue and what to do if he doesn't eat in the future. This diabetes thing is quite the ride, isn't it? Jinx is lucky to have you.

    Is there any way you could link to the article you are mentioning? I'm really curious to read it.

    I'm no math wiz, but it's just not making sense to me.

    And I believe Caninsulin and Vetsulin are the same thing. I'm in Canada, which is what Merck calls it up here.
     
    Last edited: Jun 28, 2015
  11. Larry and Kitties

    Larry and Kitties Well-Known Member

    Joined:
    Dec 28, 2009
    Can you provide a link to that article?
     
  12. Terri Monroe

    Terri Monroe New Member

    Joined:
    Jun 28, 2015
    Hi Brashworks! Jinx has two three year old kitty siblings. They are Pixie-Bobs, Pixie and Dana Stubblefield :) I found that Jinx absolutely LOVES meat baby food (Gerber only) and I can be assured he gets the proper amount of high proten food needed for his insulin!
     
  13. Terri Monroe

    Terri Monroe New Member

    Joined:
    Jun 28, 2015
    Sure thing! Here it is: http://www.adwdiabetes.com/articles/vetsulin-back

    Here is the paragraph: Remember to always check the concentration of the insulin and match the syringe to that insulin. Vetsulin is U-40, meaning that there are 40 units of insulin per cubic centimeter or milliliter. Many insulins are U-100, meaning that there are 100 units of insulin per cc or ml. Using U-100 syringes with a U-40 insulin could result in overdosing your pet. Although there are conversion tables that can be found on the internet, I strongly advise against using a U-100 syringe with a U-40 product. One little math error can have dire consequences. Use a syringe that matches the insulin concentration.
     
  14. Brashworks

    Brashworks Member

    Joined:
    Jun 21, 2015
    Interesting, and true that one little math error can have consequences but I believe that article says "overdose" incorrectly.

    This site has some great info on syringes and also go here (a Tech Update from an Australian provider of Caninsulin) where it tells you to multiply the Caninsulin (Vetsulin) dose by 2.5 to arrive at the draw value on a u100 syringe. Easy math - 10 units Vetsulin in a 40u syringe would equate to 25 units in a 100u syringe. Overdose = improbable!

    What was the volume on the u100 syringe? If it was a larger volume that would explain why the u40s looked so much smaller and indeed the markings would have been less precise - and much easier to dose incorrectly.

    I should also tell you that the actual manufacturer, Merck, has a typo on their Canadian website where it tells people to feed a cat a diet with 40% calories coming from carbohydrates - an error I have pointed out to them but they have yet to fix. One article does not a fact make!
     
  15. BJM

    BJM Well-Known Member

    Joined:
    Oct 6, 2010
    The article was incorrect - using a U-100 syringe with a U-40 insulin without adjusting for the concentration would result in UNDER-dosing the cat.
    Here's the math:
    U-100 insulin has 100 units per milliliter (mL)
    U-40 insulin has 40 units per mL; it is only 40% of the concentration of U-100. Thus, if you use a U-100 syringe for a U-40 insulin, you would need to adjust the markings to only 40% of what was on the U-100 syringe.
    Like this:
    U-100
    tick mark * 0.4 = U-40 dose
    05. * 0.4 = 0.2 units of U-40
    1.0 * 0.4 = 0.4 units of U-40
    1.5 * 0.4 = 0.6 units of U-40
    2.0 * 0.4 = 0.8 units of U-40
    2.5 * 0.4 = 1.0 units of U-40
     
  16. Terri Monroe

    Terri Monroe New Member

    Joined:
    Jun 28, 2015
    Interesting....... Just not sure why he went so hypo twice if he was getting a lower dose, but is doing just fine with the new syringes without any real other variances.... (He still sometimes doesn't eat enough, and I skip giving him insulin, but then the next morning I know by testing that he needs the insulin, so I give it to him without him eating very much, and he's fine)??? Crazy stuff I tell ya!!

    Luckily, my Vet is going to dig deeper and do some consulting and see what she comes up with. :)
     
  17. Terri Monroe

    Terri Monroe New Member

    Joined:
    Jun 28, 2015
     
  18. Terri Monroe

    Terri Monroe New Member

    Joined:
    Jun 28, 2015
    True, and so glad that my Vet is doing some more in-depth research to try and get to the bottom of this mystery!!
     
  19. Larry and Kitties

    Larry and Kitties Well-Known Member

    Joined:
    Dec 28, 2009
  20. BJM

    BJM Well-Known Member

    Joined:
    Oct 6, 2010
    He may be releasing counter-regulatory hormones which are causing stored glycogen to be broken down as glucose and put in the bloodstream to prevent him from hypoglycemia. The glycogen can be depleted, resulting in a hypoglycemic attack in the future.
     

Share This Page