Hi and welcome to FDMB.
Kudos and congrats on testing Tim. Testing is by far the best tool we have to keep our furry kids safe.
One tip for you when you get a sample but Tim gets antsy and doesn't want to wait for you to get the meter into position

..........grab the blood bead on a clean fingernail and test from there. Saves a lot of frustration for both of you.
There is lots of great information in the stickies at the top of the Lantus/Levemir forum and I encourage you to read through those documents to understand how Lantus works and our dosing methods. I notice Tim is on 2u which is a bit higher than what we would normally recommend as a starting dose. While we would normally recommend no shot unless BG is over 8.3, given the higher starting dose and lack of data as yet, I'd suggest using 11 mmol as your cut off point until you get a bit more data. Once you get more data to understand how Tim is reacting to the insulin, then you can gradually lower your no shot limit. That said, if Tim has a history of ketones or DKA, then skipping shots is not usually the best idea and I would encourage you to post for assistance.
Lantus is dosed based on how low a dose takes the BG at nadir (peak action of the insulin). Lantus' action usually onsets around +3 post shot and peaks between +5 and +7 but every cat is different, the nadir can and does move and some cats will reach nadir earlier or later. Random testing allows you to figure out your cat's usual pattern.
Getting tests before shots tells you it is safe to give insulin and tests taken during each 12 hour cycle tells you how Tim is metabolizing the insulin and how low his BG is going. We recommend a minimum of 4 tests daily whenever possible. If you are working full time, it can be difficult to get mid cycle tests every day but grabbing tests whenever you can, still provides useful data on which to make dosing decisions. We also encourage getting a before bed test every night as many cats tend to go lower overnight than they do during the day.
With Lantus, you need to know Tim will eat but you do not need to wait between feeding him and giving his insulin shot. Your routine should be test, feed, shoot and it can all be done within 5 to 10 minutes.
