You've gotten some great advice already, so I won't add too much more. Nadine's comment really resonated with me:
I hear the same desperation in your voice as I had.. I know what you are feeling. I wanted to see the numbers come down quickly and it's just not the way this works. It takes patience and time.
I felt that same way. I spent the summer of 2011 chasing Punkin's high numbers, increasing the dose (but not by large enough increments for the dose size we were at), and feeling like nothing worked. It was incredibly discouraging. Nadine's right, Lantus and Lev don't work as quickly as we'd like sometimes, but they are excellent at holding blood sugar down once you're at a good dose.
Think of changing doses like steering a barge - a small shift in the steering wheel can completely change the direction the barge is headed. Once it's nudged that direction, it will keep going strong that way. Another small shift will take a while to show its effects. With these depot insulins, you make a change, then you need to wait to let the depot catch up with the new, larger dose, and then you'll be able to see what the dose can really do in Menda's body.
The depot is an important player in our cats. The size of the depot corresponds to the size of the dose. When you increase the dose, it takes about 6 cycles or so for the depot to grow to match the new, larger dose. When you decrease the dose, it can take 4-6 cycles to have that depot decrease to "fit" the new, smaller dose. That's the reasoning for typically holding doses 6 cycles and not rushing dose increases. With a large depot, sometimes we can even skip a dose and not have it be noticed in the cat's blood sugar.
I do agree with you on the size of the increases. At 10u, it's pretty typical to increase by 1u increments. I'd just want to give it long enough to see what that new dose can do before you increase again.
Believe me, anyone with a high dose cat, or a cat that's been difficult to get regulated, understands how frustrating it is. This is a situation where slow and steady wins the race.



Hang in there! Keep asking questions. You know we're happy to help.