Hi Sharon,
I'm so sorry you're having such difficulty finding a vet to prescribe a cat-suitable insulin.
Here is an extremely helpful document:
2018 AAHA Diabetes Management Guidelines for Dogs and Cats
The whole document is very much worth reading, but for now I recommend you look at Table 1, which provides an at-a-glance summary of which insulins are appropriate to which species. Note that Novolin N is only recommended for use in dogs, not cats.
The text of the document goes further into the reasons why insulins like Lantus and Prozinc are suitable choices for treatment of feline diabetics.
I wonder whether it might be a help to you to print off a copy of the above document and to discuss its contents with some vet in your area whose treatment approach is somewhat more progressive. The document is the work of veterinary professionals, has been published in a respected journal, and therefore cannot be dismissed as something you heard from some crazy cat people on the internet. Reference to the AAHA guidelines should rightly lend greater validity to your request that Bella be treated with Lantus.
I'm sorry my previous reply to you was quite brief. I'm struggling with a really bad cold at the moment and I was absolutely exhausted at the time of posting.
I get the sense from your posts that high numbers BG numbers are quite unsettling for you (understandable), so there are a couple of thoughts I'd like to share with you:
1. Many cats have very high BG levels when they are first diagnosed. While we don't want to see our cats in high numbers, it's when a cat goes too low that there is immediate danger. This is why starting doses should be conservative. Time is needed to determine how the cat responds to the insulin being used.Thereafter, with appropriate monitoring (preshot/mid-cycle checks, BG curves) the dose can be gradually increased in small increments over a period of time to a level where the cat becomes regulated.
2. Just as the diabetes took time to develop, bringing a diabetic cat back into regulated numbers is a gradual process. It's not something that can be forced: the cat's body needs time to relearn how to run at a healthy blood glucose level. Trying to force the body back into better numbers by too aggressively increasing the insulin dose - or giving insulin more frequently - typically serves to put the cat at greater risk of hypoglycaemic episodes and, even if BG doesn't drop into dangerously low numbers, the drop itself may trigger the cat's bodily defence mechanisms to release stored sugars and synthesise more in the liver in order to protect the cat. You will often see this phenomenon described here as 'bouncing'. During a bounce, BG levels may go very high before dropping back down to 'pre-bounce' levels. In some cats it can take as many as 6 cycles (3 days) for a bounce to clear.
The idea behind the 'Start Low, Go Slow' dosing methods advocated here is to gradually and safely bring the cat back into a healthier blood glucose range by starting on a dose determined to be safe, holding it for a fixed number of days (unless the dose takes the cat too low, in which case the dose is immediately reduced), assessing the safety and efficacy of the dose, then adjusting the dose by a small increment if required. Rinse 'n' repeat until the cat comes into a better range. As treatment progresses, the cat's body steadily gets used to (safe) lower, healthy numbers.
On 8-hourly (TID) dosing of Novolin, as others above have already commented above, while it is possible to do, it is an advanced technique and, IMO, one that would require a reasonable degree of experience using insuiln before even attempting such a treatment method. It requires a
lot of testing to keep the cat safe (preshot checks before all three daily doses, mid-cycle checks on all three cycles to make sure the cat is not going too low, possibly intensive testing and feeding throughout the peak of a cycle if the cat goes too low and needs to be steered back up to safe numbers). I've only seen a bare handful of members attempt TID dosing since I joined FDMB and all of them ended up exhausted - both physically and emotionally - within a very short space of time. They were using Vetsulin, which isn't as harsh as Novolin N, and even that was extremely challenging. To the best of my memory, they were only able to stick with the TID dosing schedule for a very short time before electing to revert back to giving insulin twice a day. As I commented earlier, it really isn't a treatment approach I would recommend, not least of all because availability of longer-acting insulins effectively removes the need to even consider TID dosing.
I can completely understand your impatience to see Bella regulated - we all feel like that!

- but bringing a feline diabetic into regulation is a marathon, not a sprint. I sincerely hope that you will very soon be able to find a vet who is willing to prescribe a longer-acting insulin for Bella, and I hope you find some of the above helpful to you.
Mogs
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