Re: 5/9 Annie AMPS 356, +2-335, +4-358 - talked to vet final
Staring at spreadsheets is a good thing! (You can go cross eyed but it's a good thing!!)
I'm going to respectfully disagree with your vet. (And while he may have tons of experience with Lantus, how many of the cats he's treated have gone OTJ or are tightly regulated?) I'd try the 1.5u twice a day. Here's my thinking...
You're right -- Lantus likes consistency. One reason why shooting different amounts is often unsuccessful is that you keep "messing" with the insulin depot/shed. Every time you adjust a dose, the shed needs time to settle. If you dose different amounts at AM and PM, you never allow the shed to level off. As a result, overlap between doses is effected and you end up with very wonky numbers. Think of it as a swimming pool. You add water and there are ripples. As soon as the ripples subside, you take water away and there are then more ripples. You never let the pool reach an even level.
The other factor that isn't being taken into consideration is
dawn phenomenon. In animals as well as people, our bodies begin to prepare for the stress of the day ahead. As a result, during the night, the body starts putting out a stress hormone (i.e., cortisol) to help the body prepare. This hormone is a naturally occurring steroid and the result is that AM numbers are often higher than PM numbers. As Annie gets better regulated, the AM numbers will come down.
Having her teeth cleaned can have a huge impact on numbers. Dental issues have been known to bring an OTJ cat back from the Falls.
Your vet wants to run an awful lot of expensive tests. You might ask to have the vet prioritize the tests and to give you an estimate. I'd be frank about the expense. There may be other practical ways of determining what's needed. For example, trying Annie on novel protein foods (e.g., duck or venison) to see if that stops the vomiting. Or eliminating beef and fish which some cats are allergic to. Trying a week of Pepsid may be a far less expensive intervention if the cause is due to acid stomach.