Carole, we are looking for a more experienced member that is familiar with Prozinc to advise.
We see so many vets advising increases of whole units, and we usually see how the starting dose does for some days while gathering testing data, before making increase or decrease suggestions. Per info on Prozinc the usual starting dose is 1 U and you have not had much time to gather data.
http://www.felinediabetes.com/FDMB/forums/prozinc-pzi.24/
I think what you
may see tomorrow is higher BG again, after the lower BGs today. It's called "bouncing"
Here's an explanation of what we call "bouncing". It explains why a kitty's BG can go from low to sky high: (possibly contributing to your kitty's high BG at the higher dose he's on)
BG goes low OR lower than usual OR drops too quickly.
Kitty's body panics and thinks there's danger (OMG! My BG is too low!).
Complex physiologic processes take glycogen stored in the liver (I think of it as "bounce fuel"), convert it to glucose and dump it into the bloodstream to counteract the perceived dangerously low BG.
These processes go into overdrive in kitties who are bounce prone and keep the BG propped up varying lengths of time (AKA bouncing).
Bounce prone kitty repeats this until his body learns that healthy low numbers are safe. Some kitties are slow learners.
Too high a dose of insulin can keep them bouncing over and over until the " bounce fuel" runs out and they crash - ie., have a hypo episode. That's why we worry so much about kitties that have had too high a starting dose prescribed by the vet and the owner isn't home testing.