On this insulin, very much so. Here's a graph showing an example of an 'ideal' curve for a cat on Caninsulin:
See what I mean about bucket-shaped curves?!
In answer to your other question, yes, some cats who experience big swings in BG like this can find it hard on their systems. For example, Saoirse had a really hard time on Caninsulin, so much so that she started hiding when her injections were due in the most inaccessible place she could find in an effort to avoid them. She became really lethargic after the dose went in and withdrew behind a curtain for most of the time. She'd then perk up and be more herself for the last two hours or so of the cycle when the dose had petered out, only for it all to repeat again as soon as the next dose was delivered. As I noted in her spreadsheet at the time, it was like having two different cats. When she was switched to Lantus I got my cat back - full time! It suited her far better and she was a much happier cat for the change. (((Saoirse)))
That might be a factor in his lower AMPS values. It might be an idea to try feeding a bit more at night. He needs to get the weight back on - healthier all round.
Part of the problem with Caninsulin and the bucket-shaped curves is that very often a cat gets to the point where the nadir gets as low as it's safe to go but the preshots are still quite high and the duration is still poor. Trying to increase the dose then starts taking the nadir too low for safety and yet the cat may remain in quite a high range at preshot and in the later hours of each cycle, hence
recommendations from the likes of the AAHA to treat feline diabetics with gentler-acting, longer-lasting insulins (Lantus, Levemir, Prozinc).
There certainly seems to be a significant improvement in Oscar's clinical signs since addition of the enzymes to his regimen. The diarrhoea would have been interfering with proper absorption of nutrients from the gut, so its resolution should help Oscar get more benefit from his grub. As you note, he is spending part of the day in fairly good numbers for a newly diagnosed cat. Between the two, hopefully he might start to regain a bit of weight.
I do think that it's worth considering a switch to a longer-acting insulin sooner rather than later, specifically because spending longer in a better range might help Oscar to get back to ideal weight sooner. In terms of discussions with your vet, if you can show that the Caninsulin doesn't have long enough duration that might be the best way to oil the wheels if negotiating a change of insulin. If you can regularly grab tests around nadir time (usually somewhere between +3 and +6, but it can move around) to show how low the dose is taking Oscar, and also around the +8 mark to shed light on dose duration (or lack thereof) it would provide you with the evidence to take to your vet to support a request for a different insulin.
Mogs
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