One of the biggest lessons you'll learn with Lantus is patience. Ask
@Marje and Gracie for a pair of "patience pants."
It does take roughly 5 - 7 days fo the depot to form. It's unlikely you'll see much movement before then. Lantus is also very different than Vetsulin, although, you didn't really see Vetsulin yanking down numbers early in the cycle, which is typical of a short acting insulin. Lantus is less potent and far more gentle. As a result, Lantus does best once the dose is at a point where it can latch on to lower numbers and ideally, give Mr. Kitty a lovely flat cycle. That said, our kitties rarely read the instruction manual.
If you plan on keeping Young Again in the food mix, you will want to read up on the Start Low Go Slow method of dosing. It's described in the sticky about our
dosing methods. The other method, Tight Regulation, requires that your cat is on an entirely low carb, canned food diet. If you've not done so already, I'd encourage you to read over the sticky notes at the top of the board, The amount of information is overwhelming so please don't hesitate to ask questions.
Where in Ohio are you located? I'm in Columbus.