Welcome!
Dehydration can happen very easily with uncontrolled diabetes; it is the body's attempt to flush the excess glucose.
Take some time to read up on diet and nutrition at
Cat Info, then look at
Binky's Page for lists of canned, low carb foods that may be fed your cat. We suggest keeping the % of calories from carbohydrates to no more than 10%.
CAUTION: if your vet has established an insulin dose for your cat and you are feeding dry food, hold the diet steady until you learn to test. Glucose levels have been reported to drop 100 or more points when removing dry food from the diet.
We strongly encourage learning to home test. If you test before you give insulin, you can see if it is safe to give it. When you are first starting out, we suggest you not give insulin below 200, because you haven't established how your cat handles the insulin yet. As you collect data, you will determine what the safe lowest number is for your cat.
Lantus and Levemir insulins require dosing at 12 hour intervals and dose adjustments are based on tests during the middle of the cycle when the expected lowest point should ocurr. This is because these insulins have a carry over, or depot effect. Aside from not shooting below 200,
never adjust these insulin's doses based on pre-shot numbers.
ProZinc and PZI insulins are generally dosed on a 12 hour interval, but because they don't build up any carry over, the doses can be adjusted based on pre-shot test values.
If your vet is using Humulin N insulin, very politely request a prescription for one of these 4 insulins noted above. Humulin N lasts roughly 8 hours in the cat, and you either wind up dosing every 8 hours, or having 4 hours of unregulated glucose levels out of every 12. Prescribing Humulin N suggests the vet is out of date with regard to contemporary feline diabetes management - happens often when you have to know about multiple species and may not have treated a feline diabetic since college. If your vet is receptive, we have numerous veterinary journal articles to help bring him or her up to date.