August 22, 2000
Question from Fishers, Indiana, USA:
My 5-year old son was diagnosed with type 1 diabetes about six months ago. His diabetes team has stressed the importance of the DCCT (I believe that's what it was called), and of keeping his blood sugar levels as near "normal" as possible. Frequent calls to the diabetes team have only served to confuse the matter. In order to try to keep his blood sugar controlled, I need to figure out how much 1 unit of Humalog lowers his blood sugar, how many grams of carbs 1 unit of Humalog covers or how much 1 gram of carbs raises his blood sugar, whether any of these measurements vary from one meal to the next, and if there is a formula for determining the amount of Ultralente to give. Are there any sorts of formulas or ways of calculating these items? Every time I speak to a different person on his diabetes team, that person has her own ideas. One nurse educator said 1 unit of Humalog for every 25 grams of carbs, another said 1 unit for every 40 grams. Also, we are currently giving him his injections after he eats (Humalog at breakfast, lunch, and dinner, Ultralente at breakfast and dinner only). Would giving him his injections before give us tighter control?
Indeed there are specific formulas to calculate how much you can lower blood sugar with a unit of insulin. However, rather than using these formulas, I have had much better success with taking a more general approach to managing blood sugars. In order to be successful, you need to have a good understanding of how blood sugars respond to insulin. In addition, you need to understand that no matter how hard you work, there are times that blood sugars will not do what you expect.
Also, please understand that there may indeed be multiple correct answers to the questions you are asking your diabetes team. I would encourage you to identify a specific educator on the team (as well as physician) and direct your questions specifically to them — you are more likely to have less varieties of answers to deal with.
I usually suggest giving the injections of insulin just prior to eating — although in a 5 year old, you may be able to better decide upon a dose of Humalog based on the amount he eats which you might not know until after the meal.