look at Gus go!!!
There's one suggestion I was planning to make tonight, before I saw that Gus had dropped into better numbers. It's still worth discussing, though, because (unfortunately) he will probably bounce back to high numbers again at some point.
Gus has been sitting in very high numbers for quite a while. Lots of cats here spend a good bit of time in pink or even red when they're first starting out, but 600s have to be getting old and probably don't feel very good to Gus. Have you heard of Humulin R insulin? R is a fast-acting insulin that is occasionally used as a bolus along with Lantus. It is quick in and quick out of the system, and is very powerful. It can be used to take the edge off the very high numbers so the Lantus can work better.
Humulin R should not be used without guidance, because even a very small drop can pack a punch. Some of us here have used R with our cats, and we can help you learn to use it safely. If you're interested just let me know. Humulin R can be bought without a prescription at most pharmacies for less than $50. The vial will last a long time, pretty much forever really.
You would need the R insulin, syringes with 1/2 unit markings, and lots of test strips. Have syrup and high carb food on hand just in case. We would start during a cycle when you are home to test a lot. We would NOT start on a day like today, when Gus is lower than usual! It would be used only when he starts a bounce, just to take the edge off. What do you think?
