I’m another split doser. Don’t care what pharm reps & doctors say (& docs get their info from pharm reps anyway), Lantus never lasted 24 hours for me either. My fasting numbers were too high with one dose in the morning. First endo kept raising the dose which resulted in lows during the day, but still high fasting numbers.
Once I started taking two doses, numbers were much better. Changing to Levemir gave me even better control. I take basal immediately before going to bed & first thing in the morning. I’m also taking less basal in two doses than I was when taking one dose.
Lantus or Levemir–doesn’t deliver a steady, continuous dose. There are still peaks & valleys, but they’re just slower.