I take Lantus at bedtime and have great blood sugar readings all day until dinner. I take Humalog to cover breakfast and lunch, but by dinner my blood sugar is high. I can take anywhere from 10-15 units of Humalog at dinner time (even though not eating that many carbs), but my blood sugar continues to increase all evening long (250-300 mg/dl [13.9-16.7 mmol/L]. Why does the Lantus work great all morning and after lunch but does not continue to work into the evening? Please help because I do not want to go back to Regular and NPH.

This fading of Lantus (insulin glargine) action in the latter part of the day is not uncommon. The evidence is that the release of Lantus probably stays quite even, but that your basal needs change, which is why modern insulin pumps can be set for more than one basal rate over the 24 hours and why insulin coverage for mealtime carbs can change over the same time period.

What you need to do is either to add a small amount of NPH to the lunchtime Humalog injection at the time of the evening meal. You should work out the actual details of these changes with your diabetes team and do it gradually with careful blood sugar monitoring. You may even need to slightly reduce the bedtime glargine as part of this change.

DOB

[Editor’s comment: Of course, if you can increase your exercise in the afternoon, or decrease your noontime meal (and noontime Humalog dose), you might be able to get things under better control without extra shots.

WWQ]