Thanks for all of the quick replies.
One quick note I should have put on my original post is my cat has asthma and is on steroids for it (has been for 6 years)
Insulin Dose:
His dose has been increased in .5 to 1u increments about every two weeks (sometimes 1 week, sometimes longer than 2 weeks). If no improvement in another 2 weeks vet wants us to call back and will increase to 6u twice a day. Its been over a 4 month period so far overall.
Food:
He was on 1/4 cup twice a day of of EVO weight management food. I know that is low but it was under vet's guidance to curb a problem with continually gaining weight (was almost 20lbs at one point). He's a big cat though and vet says his weight should be around 16-17 lbs. Due to his current weight loss (he's under 15 lbs and dropping), vet has us doubling his food to 1/2 cut twice a day (he never eats all that though), and mixing the regular EVO dry which is very low carb but high cal, with the weight management. Eventually we were going to go just to the regular EVO if the weight keeps dropping. He has no interest in wet food.
BG measuring:
I was just following what the vet said, but thanks to some of the stuff I've read now realize more frequent checking is required more than just pre morning shot (and I need to do more reading). Vet never mentioned this, just said check before morning shot. Of course I had to suggest the idea of home testing to the vet in the first place. Testing before both shots is doable. However, testing 6hrs after shot is going to be difficult as I work during the day (except weekends), but I could set an alarm and do it in the middle of the night I guess. Do you need to check 6hrs after every day or just to get an initial curve?
Other Health:
The vet recently did bloodwork/urine sample, said it looked good other than signs of diabetes. Since he was acting so oddly though, she did however put on antibiotics just in case of infection.
In response to the reply on dental health, the vet said his teeth looked okay. He can't have a dental cleaning (very serious adverse reaction to anesthia).
He was on Lantus briefly (less than a month) in Dec 2009 after an immune reaction, requiring massive doses of steriods, caused his glucose to get really out of whack. In less than a month (max dose 1u twice per day and then tappered down), his BG was back to normal. We continued daily BG testing for 2 months, then weekly testing for a month, then monthly spot checking. After 6 months though of normal we stopped testing. This past November we notice excessive drinking/urnination and realized he had lost weight (2lbs), so we called the vet and started checking again. His BG was reading in the 225-285 range (one 300 reading) before we started him in insulin. Now at 5u twice a day he is having the same readings as before we started insulin.
I'm in contact with the vet every week, but she just says to be patient. So my question is what do immediately, should I call the vet about dropping the dose, or do the testing and wait and see. Would hate to think this is a rebound issue and I am causing my cat to feel so bad by giving him these high insulin doses.