What Sienne said. The other major difference between the two insulins is that the onset and nadir is later with Levemir. Lily already has a later nadir, it could be 2-3 hour later on Levemir - something to consider with how that would fit into your schedule. Some acrokitties, but not all, find they need a bit less Levemir and the cycles are flatter. But the biggest difference is the sting at higher doses, which humans have reported. Neko never purred getting her Lantus shot, she has with Levemir.