Hi Looby, and welcome to you and Smiffy.

We're in the UK, too.
It sounds like your vet is going to give you a Caninsulin Vetpen. Having bought one for Saoirse I wouldn't recommend them. They're only capable of dispensing Caninsulin doses in increments of 0.5 units and cats need finer dose adjustments than that (typically 0.25 unit adjustments are needed). The Vetpen isn't cheap, and it's very clunky and awkward to use. Conventional U40 insulin syringes are easier to use, and will give you better dosing control. Another recently joined UK member told us that their vet said that Caninsulin U40 syringes weren't available any more. I don't know whether or not this is true but VetUK are still selling U40 syringes (ÂŁ10.66 for 30 syringes plus p&p):
http://www.vetuk.co.uk/insulin-syri...in-0-5ml-u40-insulin-syringes-box-of-30-p-295
I know that you don't think it's possible that Smiffy would ever eat wet food. I didn't think Saoirse would ever eat it either but she's now a low carb, wet food only girl. It may take a little effort at first but it is worth it: better for Smiffy's pancreas (it will improve her chances of remission - becoming a diet-controlled, non-insulin-dependent diabetic); better for her kidneys and urinary tract; and you'll be astounded at how much better her coat condition will become. There is a fantastic, vet-authored site where you can learn more about proper feline nutrition, diabetes, urinary tract health, plus lots of tips and tricks for transitioning a dry food addict to a wet, species appropriate diet:
http://catinfo.org
If you need to pace wet food meals for Pasha, timed feeders can help with that (and there are other tricks we can share with you).
As others have mentioned above, learning to home test is the best thing you can do to help Smiffy achieve better glucose regulation and to keep her safe on insulin. You have the option to use a human meter or a pet meter to measure her blood glucose. Test strips for human meters are significantly cheaper than those for pet meters (your vet may tell you about Alphatrak 2 pet meters). Human meters are fine for monitoring cats' blood glucose levels as long as you use a cat-specific reference range with them (you can learn more about that here).
It takes only a short while to get the knack of home testing and it will give you much more reliable data on Smiffy's blood glucose levels (not artificially elevated due to stress, as can be the case with readings taken at the vet's practice). Another plus is that it will save you money and, more importantly, save Smiffy the stress of unnecessary vet visits because you will be able to do day-to-day monitoring and run glucose curves (a fancy name for taking a series of regular BG readings over a 12-hour period) in the comfort of your own home.
As other members above have already advised,
if you start insulin before transitioning to wet, low carb food then for safety it is VITAL that you are home testing before you start the transition because it can dramatically and quickly lower blood glucose levels and the insulin dose would need to be reduced as you go along. (Saoirse went from needing 3 units of Caninsulin down to 0.5 within 48 hours.)
Things can be a bit overwhelming in the early days after diagnosis but diabetes is most definitely do-able! I'm very glad you found FDMB: you'll learn so much here about how to help Smiffy. The moral support from the kind and friendly members here is invaluable, too.

Keep asking questions, and we'll do all we can to help you both.
Mogs
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