So I was thinking maybe dropping him down to 1.5 units starting tonight maybe tomorrow
I like that idea too. Even the 2U insulin dose is showing that it is too much, if he is dropping down to the 40's. "Feed the 40's".
Personally, if Forrest were my cat, I would not give him ANY insulin if his pre-shot BG was <150. Seriously, no insulin at all for now.
then Saturday do 1.5 with no dry food since I will be home all day again. Does this sound reasonable?
Yes, that sounds reasonable to me too. IF, and only if his BG levels are 150 or above, should you go with the 1.5U dose.
Forrest is in the tree green or neon green BG levels right now, for all of your tests. Those are normal cat BG ranges. They are saying to me NO INSULIN for right now.
Even with only a handful of tests under your belt, I think that Forrest is telling you he may be ready for an OTJ (off-the-juice, insulin being the juice) trial.
Changing one factor at a time, can sometimes let you know narrow in on what is happening. If you changed the food and the insulin dose on the same cycle, then it's very difficult to pin down which change made the difference. But sometimes you have to change multiple factors. Right now, the limited test data is telling me you need to stop the insulin.
Don't be surprised if the next pre-shot test is very high. Both the dry food and the low BG numbers could have caused those numbers to spike. Dry food takes longer to digest because it has to get wet and break down in the stomach first before it enters the bloodstream, which is why we suggest you have some high carb canned food on hand in your hypo toolkit. Something like the Fancy Feast Gravy Lover's foods are a good choice. After opening the lid, you then leave the lid on top of the can and "squeeze" the gravy (the high carb part of the food) out into a dish.
I think that Forrest is going to need another dose reduction really, really soon. Even that 1.5U dose is likely to be too much for him. Keeping all paws crossed here that he continues to be ok. When cats drop really low, they can be MORE sensitive to the insulin. Which is why I'm saying I think that even the 1.5U dose will be too high.
If you do go ahead with a diet change, eliminating the high carb dry food this weekend, you probably want to drop the dose down very, very low or stop the insulin entirely and try the diet change alone. What do I mean by very, very low? Like to 0.5U of Prozinc for a maximum. It's easier to increase the dose again in small increments, than to stay up late at night with a cat in very low BG ranges. Or have to rush your cat to the emergency 24 hour vet clinic.
So patience please. Please.