Switching from Caninsulin to PZI, what dose to start at?

Lisa and Angel

Lisa and Angel

Active Member
Angel started at 2U Caninsulin (vet wanted 3U, I felt like that was too high so they said 2U was okay too), and her numbers have been all over the place. Went up to 2.5, then 3, but she's just getting worse (both in symptoms and numbers). Went down a tad to 2.8 (roughly) a few days ago, numbers got a bit better.

I've been asking to switch her over to Lantus for 3+ weeks now, my vet was willing initially, but unfortunately we found out that it's illegal in my country until you've exhausted all veterinary med options. So we ordered PZI and waited. It finally arrived today, so I got a new Libre 2 put on her and picked up the PZI, ready to inject tomorrow.

But at what dosage? Vet said 3U, I'm thinking no more than 2, maybe even lower?

PS: If you check the spreadsheet, please take a look at the screenshots from the librelink I posted in remarks. In those first few days on 2U she went down really low.

This is my first post, hope I've done everything right! Please lmk if not.
 
I'm sorry that I don't even know what a dose of 2.8 would be. 2.75 maybe, but 2.8? how do you measure that? What kind of syringes are you using? U-40 syringes that are used with ProZinc (with half unit marking hopefully?)
 
Okay, so I am looking at the spreadsheet. First, you must absolutely get preshot tests done so that you know it is even save to give insulin at all (preshot high enough.) I don't see preshot tests. I'm sorry and I don't want to be obnoxious, but I want your baby to be safe.
 
Also, I tried the link and I wasn't able to look at the Libre data that you are referring to. How low did Angel go... and when? I need the data from the Libre at least to be loaded up to the spreadsheet if possible. I would go with a lower dose if you are in doubt and you can always increase from there and we will be happy to help!
 
2.8 mmol/L isn't the exact measurement, it's just what I estimate in numbers what I visually see on the syringe. I drew up slightly less than 3U (3U with daylight under the line, like I read here under fine dose), just to see if a small reduction would show better numbers (it did). I'm indeed using U-40 with half unit markings.

The preshots are in the AMPS and PMPS columns, or did I not do that right? Or did you mean that those need to be done every single time?

Are you able to see the screenshots if I post the link here directly? https://imgur.com/a/bbnzJCd It says that it may contain adult imagery and to confirm that you're over 18, I have no idea why it says that or how to remove it because they're literally just screenshots of the librelink app. I'm still trying to figure out how I can extract the data from the app, otherwise I'll have to transcribe it all and that might take a while. On april 22 she went down to 4.6 mmol/L (82.8 mg/dl) at the lowest, on the 2U caninsulin dose. I notified the vet but she didn't want me to reduce the dose unless she went down even further. On the 25th she hit 6.4 (115.2), on the 26th 5 (90). All nadirs. But a lot of the time she was still HI (27+/486+), and with some shots didn't have much of an affect at all, so the vet wanted me to keep upping.

She's had 2 shots of 1.5U prozinc so far, the latest one 2 hours ago. She didn't have a noticable nadir during the first shot, preshot was 22.4 and she mostly hovered around 22 (396) with one peak to HI after 6ish hours, but that might just be her adjusting to the new insulin and new dosage. Preshot from 2 hours ago was at 22.9.
 
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Yes. A preshot fasting blood glucose measurement needs to be taken every time before insulin is given. So no food for two hours prior to the preshot test (or Libre reading.). I will reply more in a few minutes. My family is waiting to eat dinner. Luckily, all cats are fed. I will be back.
 
She's freefed, so she's never fasted.

My country is lagging behind in diabetes care standards, from what I'm beginning to understand. The standard advice here is still "here's some caninsulin, start at X dose every 2 hours, bring her back in 2 weeks so we can do a bloodtest and adjust the dose if necessary" and that's it. Remission isn't mentioned as a possibility at all. I only got the libre because a diabetic friend mentioned that they read that it can be used in cats too, and bought the freedom lite meter when the libre gave out. Even then, the vet said home measurements were totally optional, and if she's been on the same dose for a while, pretty much unnecessary. Bought some ketostix when I read about ketones, and started pushing for Lantus when I read that this is the international gold standard. Unfortunately by law we have to try prozinc first, and only if that doesn't work well enough yet we will be allowed to try Lantus.

Take your time, enjoy dinner!
 
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Lisa and Angel said:
She's freefed, so she's never fasted.

My country is lagging behind in diabetes care standards, from what I'm beginning to understand. The standard advice here is still "here's some caninsulin, start at X dose every 2 hours, bring her back in 2 weeks so we can do a bloodtest and adjust the dose if necessary" and that's it. Remission isn't mentioned as a possibility at all. I only got the libre because a diabetic friend mentioned that they read that it can be used in cats too, and bought the freedom lite meter when the libre gave out. Even then, the vet said home measurements were totally optional, and if she's been on the same dose for a while, pretty much unnecessary. Bought some ketostix when I read about ketones, and started pushing for Lantus when I read that this is the international gold standard. Unfortunately by law we have to try prozinc first, and only if that doesn't work well enough yet we will be allowed to try Lantus.

Take your time, enjoy dinner!
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What country do you live in? Many vets in this county tell their clients the same thing — do not test — just look at the clinical signs, etc. vets in the United States receive very minimal training in diabetes at all — let alone Feline Diabetes. I an happy that you are educating yourself on the best way to manage things and help your cat.

The reason for withholding food for two hours prior to the AMPS and PMPS (a.m. and p.m. preshot tests) is to ensure that the number is not influenced by the food they’ve been eating— meaning that, if they’ve been eating, the BG number will be higher because of the food. If you shoot insulin on a food influenced number then the food may wear off and your cat’s blood glucose may drop too low. So the AMPS and PMPS tests are to make sure that it’s safe to even give insulin (i.e. they’re not too low) and to see if it’s necessary to give a reduced dose for that cycle because the BG is too low.
 
Oh, and regarding vets who tell their clients not to monitor BG at home: Many times a cat who is hypoglycemic will not show any signs at all of having too low blood sugar— at least until they get into very dangerously low BG. So you cannot tell just by watching the cat with your eyes, you have to test.
 
Stick with the 1.5 units of ProZinc for now — for a total of 7 days (unless Angel drops below 90 and then that earns a mandatory .25 unit reduction in dose for the subsequent cycles.) Don’t increase the dose. We need to stabilize things. It looks like your kitty is bouncing for now. Keep watching for him to clear the bounce and blood sugar will go down. I understand how hard it is to wait!!
 
I live in The Netherlands. She always has access to food, eats small amounts frequently so it doesn't really get the chance to wear off. I currently do not have the ability to withold food for 2 hours before every shot.

I'll stick with the 1.5U prozinc! Made her spreadsheet up to date again too. I've read the link!
 
Okay. Right now it is not critical that she be fasted for two hours before the preshot test but only because her numbers are so high. When she gets down into more normal numbers it could be a problem. Let’s say she has a preshot of 100 or 150. How will you know, since that number of 100 or 150 is safe to shoot? We won’t. Because the number can’t be trusted because it is inflated by the consumption of food.
 
Now, having said all that (which is just an explanation and not a criticism) I understand that sometimes people have constraints on them that hamper things.

Do you have other cats? What is your schedule like? Work schedule? I’m asking because it can be important especially when feeding and testing are necessary. So far you are doing a great job
 
It does look like she is going to need an increase to 1.75 after we have tried this 1.5 dose. But let’s let things stabilize for her body. It’s hard to wait, I know. What proportion of wet to dry food does she eat? Would you be able to estimate? Do you know how many carbs are in her dry food — and her wet food?
 
Hi! Big message incoming to answer all your questions.

Okay. Right now it is not critical that she be fasted for two hours before the preshot test but only because her numbers are so high. When she gets down into more normal numbers it could be a problem. Let’s say she has a preshot of 100 or 150. How will you know, since that number of 100 or 150 is safe to shoot? We won’t. Because the number can’t be trusted because it is inflated by the consumption of food.
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But if she always has food in her belly (she eats small meals many times a day), doesn't that mean the 'inflation' by food is a steady constant influence that never goes down, since it's constantly being consumed?

Now, having said all that (which is just an explanation and not a criticism) I understand that sometimes people have constraints on them that hamper things.
Do you have other cats? What is your schedule like? Work schedule? I’m asking because it can be important especially when feeding and testing are necessary. So far you are doing a great job
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Yes, I do have other cats, unfortunately with health problems of their own. I work from home, but am dealing with a chronic illness that leaves me sleeping 14+ hours a day. I set alarms to wake myself up at insulin times, and in between to scan the libre/check her with the regular monitor when she doesn't have the libre on, and keep myself up whenever I think she may be going for a hypo. But tbh, it's been really rough. Luckily she's an absolute sweetheart and the most typical ragdoll ever, very tolerant of the tests and shots, so that makes it bearable.

It does look like she is going to need an increase to 1.75 after we have tried this 1.5 dose. But let’s let things stabilize for her body. It’s hard to wait, I know. What proportion of wet to dry food does she eat? Would you be able to estimate? Do you know how many carbs are in her dry food — and her wet food?
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She has unlimited dry food, one variety has 5% carbs, the other unfortunately has 13% carbs; one of my other cats refuses to eat the 5% food, and has health issues of her own that require her to be able to freefeed. But she's already acting picky about the 13% food now, so I might have to hunt for a new dry food soon that I can leave out.

They gets wet food 1 to 2 times a day, in a big portion so they can eat from it for a few hours afterwards until it's all finished. That's all low cal, some super low (0-4%), some a bit higher but still low (<8%). Some days she likes the wet more, some days less. So I think proportion wise it differs between 60:40 dry:wet some days, to 80:20 other days.
 
The spreadsheet is up to date again. Notably, she had a big drop on the 28th. These weird unexplained drops happened on the caninsulin as well. The other days she's been steady high.

I had a check up with the vet today, they advised me to go up to 2U tomorrow. What do you think? I proposed the 0.25 increase you said, but they said that'd be too little to make a difference.

We also had a look through her medical file, as she's been through lots of treatments for her (unrelated to diabetes) neuropathy. And we saw that in late january, she had a Moderin (methylprednisolone) shot! I've read that steroids given <6 months prior to diagnosis are associated with much higher odds of remission, I hope I can get her there.
 
.25 can make a difference. I’ve seen it make a big difference many times on many cats. Because of the blue nadirs the other night, if she were my cat, I wouldn’t do a full .5 unit increase. If all nadirs are 300 or over, it would be okay.
 
She’s been bouncing from the blue numbers ever since. It can take six cycles to clear. I would wait until a full six cycles to increase.
 
here’s some information on bouncing in case you’re not familiar. I am not sure how many of the Sticky notes on this ProZinc forum that you have had a chance to read.

Bouncing
Bouncing is simply a natural reaction to what the cat's system perceives as a BG value that is "too low". "Too low" is relative. If a cat is used to BGs in the 200's, 300's, or higher for a long time, then even a BG that drops to 150 can trigger a "bounce”. It should be noted that “bouncing” is a term we use in the FDMB and might not be recognized elsewhere.

Bouncing can also be triggered if the blood glucose drops too low and/or too fast.The pancreas, then the liver, release glucagon, glycogen and counter-regulatory hormones. The end result is a dumping of "sugar" into the bloodstream to save the cat from going hypoglycemic from a perceived low. The action is often referred to as "liver panic" or "panicky liver". *Usually*, a bounce will clear kitty's system within 3 days (6 cycles). You cannot avoid all bouncing. It is normal and natural, and frustrating. There are some things to keep in mind that can help though:
  • Following a bounce, a cat’s BG may stay high and flat for several cycles. Avoid the temptation to increase the dose at this point. If the BG does not return to normal in 6-8 cycles, an increase might be needed based on the method of regulation you are following.
  • Some vets might have little/no understanding of the bouncing phenomenon. Consequently they will look at a single BG number or a single in-office curve and change the dose without realizing that they could be looking at a bounce number, or a high-flat cycle following a bounce, and increasing the dose will make it worse.
  • There is also a common misconception, often by vets, that bouncing is caused by chronic Somogyi rebound. Michael Somogyi published one paper based on a very small number of human diabetic subjects on the topic in 1938 in a local St. Louis medical journal. There has been no replication of the research and, in fact, anyone that has attempted to replicate the research with humans failed to find similar results. The research has never been done with cats and, just as importantly, has never been done with cats (or humans) using a long-acting insulin.
  • When it’s not a bounce: in general, during a cycle, the blood glucose should decrease for a few hours, and then begin to increase again. If you plot the numbers on a graph, they should look like a smile. This rise in BG towards the end of the cycle is normal. It is not bouncing. As a cat gets better regulated, the cycle will get a little flatter and the PS numbers will decrease, but in the beginning, it can feel like that rise at the end is a bounce. It often isn’t. It’s just the insulin losing duration. As you slowly reach a better dose for your cat, the insulin will last longer and the numbers will look better.
 
Thanks for the info! I did read all the stickies, but it was a lotta info at once so I think I'd better read them again.

Do you know what would cause such a drop unexpectedly?

I did end up giving her 2U for her PMPS shot today:arghh: but it was after 5 cycles had passed, so hopefully that was okay. Her BG wasn't really flat these last few days, just high. Her next shot's in 2 hours, should I continue this dose?

Here's her graph today from the libre (last 24 hours, latest shot was the 2U one):
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Don’t worry. I think it will be okay. Keep with the 2 units for now as long as you can monitor the cycles carefully. And with the Libre you can monitor. She’s been very high and fairly flat lately. So perhaps we will see something better with the 2 units.
 
I think so too! Am I wrong to think the fairly flat curve might be a good thing? I'm hoping we can get it down gradually into the green numbers while staying fairly flat. She seems to be feeling better when not having such big ups and downs in the BG, even though it's still high.
 
I've finally managed to get the data from the libre, and filled in ALL the numbers since the start (up to right now).

To be honest, I'm feeling pretty discouraged. Her prozinc numbers look so bad compared to the caninsulin numbers... But she clearly felt awful on the caninsulin, and I thought prozinc would be better. She seems to feel better. But her numbers are so high!

I'm wondering if it would help to switch over to the modified prozinc method to up her dose quicker? Or should I just be patient some more and stay on the 2U? I can monitor her very closely with the libre. If you say wait, I'll wait. I want to help her, but I'm worried I'm messing it all up.
 
Hi there. Thanks for entering all that data. It really is distressing to see all those high numbers on her spreadsheet. I understand. Can you try to hold onto this dose for a few more cycles? You say she seems to feel better? That’s a good sign. Sometimes you see them start to feel better before you see the numbers come down.
 
I can do that. And yes, she seems to be feeling better. Drinking less, pees smaller/less frequent, more active again (spending more time in the yard, and also bothering me for cuddles again). I'll keep you updated for the next few cycles!
 
Lisa and Angel said:
I can do that. And yes, she seems to be feeling better. Drinking less, pees smaller/less frequent, more active again (spending more time in the yard, and also bothering me for cuddles again). I'll keep you updated for the next few cycles!
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This is good news. Those are real improvements in her quality of life. Yes, do write here any time this weekend. I will be checking my email and should get alerts about any updates on this thread.
 
Finally in the yellow again today, after a wacky AM that just dropped and didn't climb back up. Hoping for no red this cycle!
 
The libre stopped working today. I'll keep testing preshots with the freestyle, but I'm unsure about when to do spot testing because she's not showing a regular nadir yet. What would you do?
 
I have requested a replacement, but it'll be a while before it's delivered. I was thinking of upping her dose tomorrow or tuesday, does that sound okay? I'll do a curve during the first dose and hope we'll see a nadir.
 
Did I ask you this before? Are you testing for ketones at home? I’m hoping she doesn’t have any in her urine. I used a blood ketone meter, but most people buy urine ketone strips and put them into the stream while their cat is going.
 
Wow. A yellow AMPS. I would wait until Tuesday to increase. Doses with SLGS should be held for 7 days. Just try to get some +2 or 3 and try to check around +6. Maybe we will start to see a nadir soon. Hopefully your Libre will be replaced soon.
 
Agreed! I'm hoping to see some blues again soon, and maybe even some greens.

I also wonder if the libre was registering consistently higher than the freestyle- at one point, I did do a comparison and there was a difference (libre said 21.9, freestyle said 17.6) but during the blues I checked again and the numbers matched. So I chalked it up to an error reading. But now I wonder...
 
Lisa and Angel said:
Agreed! I'm hoping to see some blues again soon, and maybe even some greens.

I also wonder if the libre was registering consistently higher than the freestyle- at one point, I did do a comparison and there was a difference (libre said 21.9, freestyle said 17.6) but during the blues I checked again and the numbers matched. So I chalked it up to an error reading. But now I wonder...
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I definitely have found that the Libre reads lower st the lower end of the scale. And I have heard a lot of people say that the Libre reads higher at the higher end of things. So maybe blues are in the middle? The Libre measures glucose in the interstitial fluid and not actual blood glucose. I have heard people here say that there is a 15 minute lag time before the Libre readings catch up with the meter readings. It’s enough to make your head pop off!
 
Yes it definitely is. It's a shame I didn't have the freestyle during that first drop into green on the libre, as I'd like to have known how accurate that was. Maybe next time though.

And another pretty yellow this AM, this is the lowest preshot she's ever tested! Hoping she's not gonna dive too hard or too low, but I have some HC food (and honey of course, the full hypo kit) at the ready if she does.
 
Any news on when you will be able to get your Libre back? I see you are getting more consistent yellows and that's good. I hope for even better things now that you've increased to 2.25 units.
 
May I ask you about Angel's neuropathy? What is the cause of this neuropathy? What kind of neuropathy is it? (I mean, how does it manifest itself and what kind of problems does she have from it?) Is it controlled by the Pregabalin? She is incredibly beautiful, by the way!
 
Based on the last time, it's probably gonna take a week for me to receive a new Libre. I like seeing the yellows! There seems to be a downwards trend, so that's good. Hoping we can keep the relatively flat curve all the way into the blues and greens.

As for the neuropathy, she had surgery several years ago that unfortunately resulted in nerve damage. She began to self mutilate on the scar tissue, and has hyperesthesia-like symptoms in addition to the biting and excessive licking.

We started with gabapentin, and that controlled it for some time, but it seems to be progressive and eventually Gabapentin wasn't enough. Pregabalin (longer and stronger duration) did the job for the next few years, but it gradually started helping less and less as well. Both the Gaba and Pregabalin also have an appetite stimulating effect, which caused her to overeat and become heavier and heavier, no doubt contributing to the diabetes. Her quality of life is still decent, but not as good as it should be. That's a constant in the back of our minds.

We've tried some more experimental stuff, including a steroid injection into the scar tissue this january. None of it helped very much. Then the diabetes started, and the neuropathy was put on the back burner for a little bit as she was losing weight extremely rapidly. Now that she's doing better with the diabetes, we're looking into what options remain for the neuropathy. Topiramate looks promising, based on a few small clinical trials of cats who also self mutilate due to neuropathy. We're hoping to start her on that soon. In addition to the analgesic effects, studies on rodents have also shown really promising effects on type 2 diabetes (reduces plasma glucose levels and improved insulin sensitivity), so it'll be really interesting to see if that applies to cats as well. It also reduces appetite, so that'd be great to get her to lose some weight as well.

And thank you for the compliment! She's gorgeous and so sweet. I hope I can give her her health back, she deserves it.
 
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I have read about Topiramate being used for feline idiopathic ulcerative dermatosis. Is that what she has? I read it was characterized by self-injury/trauma. So is hyperesthesia. I wonder if they’re using any similar anti-epilepsy drugs for that as well?
 
That's not exactly what she has, though I think that's because it's still mostly controlled by the Pregabalin. When not on that, she will bite and tug at the skin with her teeth, no doubt that'd eventually cause injury if she was ever off her meds long enough (never tried to find out). When on the Pregabalin, she just has licking episodes randomly throughout the day.

Here's the link for that feline idiopathic ulcerative dermatosis study: https://d.docksci.com/topiramate-in...atitis-in-a-two_5ae5371ad64ab2e6f88b881d.html (the PDF reader is easier to read than full text). Based upon the clinical signs and response to treatment, the authors propose that this syndrome may be a neuropathic itch syndrome. Here's another small study that's a quicker read: https://www.researchgate.net/public...to_manage_post-traumatic_mutilation_in_3_cats

We've never been able to determine whether what Angel feels is pain or itching; our initial vet was convinced she was itchy, our current vet believes it's pain. We can't ask her, and they're both bad, and they have similar treatments anyways, so it doesn't really matter. The fact that even cats with more severe self inflicted trauma respond well to topiramate, is a good sign that Angel might benefit as well.

I wonder if they’re using any similar anti-epilepsy drugs for that as well?
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Yes, I believe more and more vets are doing this! Gabapentin and Pregabalin are both anticonvulsants, and are well known and used more and more for these such conditions. Phenobarbital is a common one as well that I've read is used in the treatment of Feline Hyperesthesia Syndrome.

Newer/less known anticonvulsants like topiramate haven't been studied in pets much/yet, so that's more experimental I believe. I'm willing to go for it because her quality of life demands finding a solution, but I imagine that's not necessary in most cases.
 
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