Hi Mary,
I see you've reduced the Vetsulin dose. Be sure to keep your vet in the loop on the nadir BGs and dosing, and also make sure you check regularly for urine ketones.
Looking at Marmalade's pattern of response to Vetsulin with the data currently available it looks like he tends to be at his lowest somewhere between +3 and +7 after the dose was administered so that might be the best window for testing. If he were mine I'd want to get a +3 'before bed' test at minimum each PM cycle for safety. If the +3 is on the low side it would probably be advisable to test again later in the cycle to see just how low he goes.
It may take several cycles before you start to see what the 1.25IU dose is doing.
If the 1.25IU dose doesn't work well enough then it might be time to consider whether switching to a longer-acting insulin with a 'gentler' action profile (Lantus or Levemir) might work better for Marmalade than Vetsulin. (The 'L' insulins are typically better at holding numbers down in better ranges for longer and, again typically, don't tend to drop BG as fast and as far as Vetsulin tends to do at onset.) I'm only mentioning this as a possibility to consider for now.
Mogs
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