In very generalized terms, I would agree that it is not uncommon to see insulin requirements diminish during the time of a gastrointestinal illness. I have seen insulin requirements go down a few days BEFORE such an illness and certainly during and for a few days after. If the appetite is down and/or the intestinal system is not digesting/absorbing nutrients properly, you can see why less insulin might be required. But do NOT stop insulin as this can lead to Diabetic KetoAcidosis (DKA). I’m glad to read that you’ve been checking for ketones.
You described your child having “a stomach bug” but unfortunately, I don’t know what that really means. Vomiting? Diarrhea? Both? Fever? Other symptoms? What other medications did he receive? What has his overall glycemic control been? The answers to these questions might allow a more detailed response to your good question. Note that it is usually a gastrointestinal illness (as opposed to a respiratory flu, for example) that may lead to such dramatic changes and short-term reductions in insulin needs.
If this has been your son’s first gastrointestinal bug since diagnosis two years ago, then it may be prudent to review some “sick day management” ideas with your own pediatric diabetes team.
DS
