I've been writing this for the last hour
l kept getting interrupted by the furballs at home, everyone is locked indoors, Saturdays are hunting days, I already have a cat whose full of shot, a lame le
Firstly, how are you doing? Are you getting enough rest? It's been a 'busy' few days.
How is Fistuk generally? Is he putting weight on? Is he slowly eating more? nice that he sat up to eat yesterday. (U answered that already

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Congrats on the reduction, a drop into the 30s gave you no choice. I hope that the new dose keeps him I greens without dropping him too low.
I'm not convinced that yesterday's low was because 4.5u was to much, personalky I think that the depot from the higher doses and instability of shooting different doses may have had something to do with the numbers you got. 8t wouldn't surprise me if he ended up coming g back up again. Hopefully I'm wrong, and 4u is perfect for him and you see a sea of healing dark greens.
Just a FYI and for anyone reading your condo usually on TR, when a cat is on less than 5u bid, we take 0.25u reductions, even if they dropped into their 30's, , in Fistuks case their are other factors that are being considered at this time, both for his reductions and increases.
- He's not eating so well, you have been having to assist feed
- You've been fighting lows
- He had some glucose toxicity which has resolved, hence the sudden change in numbers.
- He's had DKA
- You're his sole carer,
Taking a dose down too quickly can be as counter productive as taking it up to quickly. In an ideal world what we are aiming for is a week in numbers normal for a healthy cat (50-100) before we take a dose down, that of course is often out of our hands, but IMO it should be what we aim for.
You've been getting great guidance and advice, I'm not suggesting otherwise, for your current situation. It's just that I wanted to make clear that going of protocol is not done lightly.
I gave George a maintenence dose of s. Bouldarii once a day for about a year. Not because he had a problem, his stools got to be normal after about a month, but because he'd had a very long course of antibiotics, and I wanted to give him a chance to fully recuperate. As continuing S.boull was not harmful and can be beneficial I erred on the side of caution.
I can't remember how long I gave the emergency dose fir or if its OK to continue it for longer.