My seven year old son, diagnosed with type 1 diabetes about a year and half ago, wants to stay overnight at a friend’s house. It would be nice if we could draw up the insulin in the evening for his morning injection (he gives his own injection because, at age seven, we don’t feel he is mature enough to draw up the insulin). How long is a mixture of Regular and NPH insulin “good” in the syringe?

I agree that a seven year old is not mature enough to reliably draw up his own insulin. There is no reason why you cannot pre-draw it and keep it refrigerated until it is time to be given, Visiting nurses do this all the time for the visually impaired, and the insulin should be stable for about two weeks. You may see some slightly higher numbers because of binding of the NPH and Regular, but so what? It won’t hurt a great deal, and psychologically, being able to stay at a friend’s house is very important. There are a few additional things you should think about, however:

It is essential that the parents of your son’s friend know the causes recognition, and treatment of hypoglycemia.
Because of your son”s insulin regimen, make sure these parents understand the importance of timing and content of meals and snacks. It is might be helpful to go over a menu with them ahead of time.
Make sure you will be easily available (at least the first time) should there be any questions or problems.

SS