Boots diagnosed ~18 months ago, on Lantus 3u until past 4 months, then 2.5u. Went in for annual visit 2/9, BG 67, 1 hour after insulin. No insulin since then (per vet). Fructosamine 2/21 182. Did a spot check today, BG 568. Called emergency vet, she suggested 2.5u and contact usual vet in a.m. I'm thinking lower initial dose? And, what is the really scary number for high BG?