Mixing Insulin

[Diabetesnet.com]

Hello: My daughter was diagnosed with Type 1 diabetes in August 2009. There is a strange pattern, every night the BG rises and falls in the morning. The BG test at bedtime is ok, the BG test in the morning is ok, but the BG over the night is high.
The doctor has changed Lantus (1 Per day) to Levemir (2 per day), and he said that we can mix Humalog and Levemir in the same syringe, to decrease the number of injections. But in Levemir´s Indications read : “Never mix Levemir with other insulin products”.
I read the book “Using Insulin”, in chapter 5 appears the table with the Insulins that can be mixed in the same syringe.
What is the origin of the table? Is there any publication on this?
Regards

[John Walsh, PA, CDE]

On the strange pattern, does your daughter have a bedtime snack that might cause this rise? Here, the bedtime carbs would cause the rise and her Levemir catches up toward breakfast.
If she doesn’t have a snack, the pattern would appear to be odd. Because of the relatively short time she’s had Type 1, she may produce enough insulin to bring down a middle of the night high reading with her own insulin production. In other words, her Levemir dose is too small, but she compensates with her pancreas once her reading rises. One clue to this possibility would be that her total dose of Levemir for the day would be quite a bit lower than her total dose of Humalog.
Using Insulin was written before Levemir was available in the U.S. and it was believed that it would be possible to mix it with short acting insulins. However, we’ve since learned that insulins like Humalog may interact with albumin, a carrier in the Levemir bottle, and also possibly form hexamer complexes that may slow it down.
If the two insulins are mixed and injected right away, this lessens any interaction between the them. Mixing obviously reduces the number of injections (a pump greatly reduces injections), so if you mix them, check her post meal glucose results. If her 1 and 2 hr post meal glucoses are OK and her readings are relatively stable through the day, then mixing the insulins is OK.
Update us on this,
John