My son is 6 years 9 months old and was diagnosed about 2 years ago. My endocrinologist has just advised that my son is being overinsulinized (receiving 1.9 units/kilo, 49 units/day). He weighs 25 kilos and wants to reduce to 1 unit/kilo. Is this common? Why has the ratio been raised to this extent without coming to this conclusion prior to today?

In the absence of a lot more in the way of a detailed clinical history it is not possible to do more than make some tentative suggestions as to what to discuss with your son’s endocrinologist. To begin with, you should be quite sure that his insulin requirements really are 1.9Units/Kg/day: I imagine that you yourself are still giving all injections and that there is no evidence of error in the meter or the bathroom scales. If this proves to be correct then he really is needing a little over twice the normal insulin requirement at his age.

The most frequent cause of this by far is that the insulin dose has been slowly increased in the pursuit of better control of blood sugars: this in turn may lead to a significant increase in appetite and weight gain. In turn the extra carbohydrate intake can necessitate an increased dose of insulin and obesity may bring about some insulin resistance as well. This state of affairs can sometimes be put right very quickly by an abrupt reduction of the insulin dose to conventional levels.

A very much less likely reason is that he has one of the many forms of insulin resistance such as Type A insulin resistance or some distortion of the sensitivity of the insulin receptors; the diagnosis of which will require some special tests.

DOB