Oh,
@Pads&Ro (Are you Ro? I'm guessing so..but don't want to presume too much...

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A few afterthoughts...
You may find some helpful general info in the links in my signature (at the bottom of this post).
The first link is to a list of low carb foods in the UK. We recommend that kitties eat foods that are less than 10% of calories from carbs. But if your kitty is currently on a higher carb diet then it is
super important that you learn to test blood glucose at home
before lowering the carb content of the diet. Lowering carb content of the diet can reduce blood glucose considerably in some kitties, and the insulin dose may need to be reduced accordingly so as to avoid hypo. Hypo can kill...
The second link is to a compilation of info for UK newcomers to feline diabetes (although I know that you are not 'new' to diabetes, just new to this forum).
And regarding switching to lantus from Caninsulin (or Prozinc). There are differences in these insulins which you'll need to be aware of. So
do read the info stickies at the top of the lantus/lev subforum. (Get a cuppa and get comfortable first...


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Key differences include things like how the insulins actually work.
Caninsulin is an 'in and out' insulin and is invariably gone from the system well within 12 hours (often much less); Prozinc can have a slightly longer duration. Lantus is a 'depot' insulin. This means that when you inject it some of that is used in that same insulin cycle, but some is stored under the skin (the 'depot', also known as the 'shed') and is released slowly over time. It can take a number of days for the 'depot' to build to its optimal level for any given dose, so you won't see the full effect of any dose until the input/output of the depot has become established.
If you draw too much insulin into the syringe you can't put that back into the vial when you're using lantus as you might do if using Prozinc or Caninsulin. So, you'll need to eject any excess onto kitchen paper, or into the sink, or dramatically into the air, haha!
Lantus requires greater consistency with regard to the timing of the insulin shots, and the dosage itself. Prozinc and Caninsuln are more 'flexible' in this regard, but with depot insulins you always have to consider the effect on the insulin 'depot'.
Eliz