He weighs about 16 pounds (down from 18) and probably should weigh about 12 ....Would Purina DM be a better choice or about the same?
No, it is still high carb and quite expensive ... most of us feed Fancy Feast Classics or Friskies pate BUT anything
on this chart that says 10% or less (ideally under 5%) is fair game for a diabetic.
You'll also find that Purina DM is mostly liver and cats tire of it quickly ... so you'll end up with expensive food that they don't want to eat after a while.
With diabetics, you do of course need to trim the kitty down, but they also need more food than normally recommended, oftentimes double. So if he should weigh 12 lbs you'd feed 240 calories x 2 = 480. An unregulated diabetic won't be utilitizing food properly hence the need for extra calories plus peeing alone will make him lose the calories he eats. Another rule of thumb might be to feed the ideal body weight in calories (240 cal) plus an additional 3oz of food. I wouldn't recommend trimming him down too fast, you don't want cats to lose more than 1% of their body weight a week.
As the others said, Vetsulin needs to wait 20-30 minutes after food is on board since it hits hard and fast. Don't really recommend Vetsulin, it's meant for dogs. Cats should be on Lantus or Prozinc (we can help you get Lantus cheap, it's very expensive in the US). While on Vetsulin, I do recommend testing and feeding 1 hour after injection, as it hits cats hard and fast and often causes problems due to how it reacts in the body.
Whenever you have time, jt and trouble's (Jeanne's) post above with information getting started would help us help you get your kitty in check!
