Welcome to FDMB, Adrienne! This is truly the best place you never wanted to be.
Great job getting started with home testing and getting Eli's spreadsheet (SS) started. As others noted, you're vet started you on a good dose of Lantus but gave you the standard vet info on food. We advocate for a species appropriate diet that is low in carbohydrates (i.e., under 10% carbs). However, most of us feed less than that 10% -- usually somewhere in the range of 4 - 6% or even lower. As a comparison, W/D is 25% carbs for the canned food and 37% for the dry. I have no doubt this is why you're seeing such high numbers. In fact, the effect right after your shot this morning in notable.
If you have a supply of strips for your meter and will be home this evening to monitor, I would get rid of the prescription food. (FYI: your vet or the store where you purchased the food should take it back. Most of us have been through this before coming here. Just say your cat won't eat it.)
At the beginning of this process, testing every 3-hours (i.e., a "mini-curve") is helpful so you have a sense of when Lantus onset begins and where Eli's nadir (lowest point in the cycle) falls. As you collect test data, this pattern will become more evident.
I'd also suggest you read the starred, sticky notes at the top of the Lantus board. These notes contain the following information:
- Tight Regulation Protocol: This sticky contains the dosing protocol that we use here. There are also links to the more formal version -- the “Tilly” Protocol developed by the counterpart of this group in Germany, which was also published by Kirsten Roomp & Jacqui Rand, DVM in one of the top vet journals.
- New to the Group: Everything you wanted to know about this forum and more. Info on our slang, FAQs, links to sites on feline nutrition and to food charts containing carb counts, how to do a curve and the components to look for, important aspects of diabetes such as ketones, DKA, and neuropathy, and most important, info on hypoglycemia.
- Handling Lantus: how to get the maximum use from your insulin and what to not do with it!
- Lantus depot: This is an important concept for understanding how Lantus works.
- Lantus & Levemir: Shooting & Handling Low Numbers: What data you need in order to be able to work toward remission or tight regulation as well as information if you have a low pre-shot number or a drop into low numbers during the cycle.
One other suggestion might be helpful. Given that Eli has been sitting in higher numbers, it would be prudent to test for ketones. This is much easier than testing or giving insulin although you will need to stalk your cat to the litter box. You can purchase urine ketone test strips, Ketostix, at most pharmacies. You follow the instructions on the box and pass the paper end of the strip through your cat's urine. The paper will change color after 15 seconds (see the box) based on whether ketones are present. There is a color code on the container for you to compare with. Ketones are dangerous and an unfortunate complication of diabetes.