Hi Lee,
First up, the 2.75IU dose is too high and needs to be reduced again. Second, with a history of ketones in the mix, it's critical that Venge eats enough. He's underweight so it's OK to let him eat throughout the cycle - with the exception of the two hours before each preshot BG test is due (needs to be a fasting BG test).
Changing to an exclusively low carb diet can potentially drop the overall BG range by around 100 points.
I think the removal of the dry kibble for grazing is part of why Venge's dose keeps needing to be reduced.
The insulin is definitely working but because you've reduced the carb load it's taking him down to a range that's too low when the insulin is working at peak effect, and he now needs to race down the insulin dosing scale.
I strongly recommend you test for ketones ASAP, just in case this might be nausea-related behaviour (cats throwing ketones can become nauseated). See checklist of symptoms here:
Nausea symptoms and treatments
Urine test strips are cheaper but blood beta ketone meters (pricey strips) are great because you can test on demand and don't have to wait to collect a urine sample (trickier again in a multi-cat household). Also, BBK meters can detect ketones sooner. See:
Ketones, DKA, and ketone meters
Tips for collecting urine samples
Given that Venge was hospitalised for several days to treat ketones there's a definiite possibility he had diabetic ketoacidosis (DKA). I suggest you ask your vet to confirm whether or not Venge was treated for DKA. If DKA is confirmed, there is usually some infection, inflammation or other systemic stressor present and that needs to be identified and treated, so also check this with your vet.
Cats who have a history of throwing ketones are typically more prone to them going forward (particularly if they're underweight). It is critical that ketone-prone kitties get enough food and insulin to keep ketones at bay. It's also a really important safety precaution to test daily for ketones. Any higher than trace means one needs to seek veterinary advice/treatment immediately (ketosis and DKA are medical emergencies).
It's sometimes better to feed cats recovering from an episode of ketosis/DKA a medium carb diet for a while so as to ensure they get enough insulin every day. Such a regimen may also help a kitty to regain lost weight. If Venge continues this race down the dosing scale, I am wondering whether you might need to bump his carb load up a little again - especially if he's not reliably eating as much as he needs to - to ensure he gets enough insulin to keep ketones at bay and makes a solid recovery from his earlier ketone episode. (
@JanetNJ - what do you think?).
After a skipped dose, in general one waits till the next scheduled shot time. It's not a straightforward thing to skip insulin for ketone-prone kitties. If preshot BG is lower than normal or if appetite is iffy, it may be possible to give a token dose of insulin. Please ask your vet to give you guidance on dosing in such a circumstance and also post for help here.
If you did skip a dose and then gave insulin, say, 6 hours later, you would then need to wait 12 hours before giving the following dose (i.e. your whole schedule would change, and to go back to the old schedule you'd then need to adjust each shot time by 15 minutes until you eventually get back to your normal schedule).
Two, possibly three, pees a day is fairly normal PROVIDED the volume of urine voided isn't excessive and PROVIDED the cat is drinking enough. With diabetics it's tricky - especially when, like Venge, they're spending time over the renal threshold (est. 200-230 on human meter). When over the renal threshold glucose is excreted in the urine and that also draws extra water out of the cat's body, creating the potential for it to become dehydrated. It's advisable to regularly check for dehydration (check gums to see if they're sticky, or pull up the loose skin round the scruff/shoulder area into a tent and release - if gums are sticky and/or skin is slow to return to normal position or remains tented then the cat is dehydrated). Excessive vomiting and diarrhoea can also lead to dehydration.
Mogs
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