We need to know, after 10 years of type 1 with our tall, skinny 17 year old son, it is is safe to say that every time a child with diabetes vomits, it does not have to be a panic situation, especially if no ketones are present? Just recently, our son vomited once, so I tested and watched him every 30 minutes for nine hours. Surprisingly, his numbers were great throughout the night, even without food. How could he vomit and not need extra food to cover the loss? Currently, he takes 46 units of Lantus at 10 p.m. and one to seven units of NovoLog after meals.

I think if you ask 10 pediatric endocrinologists your question, you might get a couple of opinions. But I’ll give you mine.

I think you are correct: an episode of vomiting is no need to panic. Heck, an episode of high glucose or low glucose is not typically need to panic either. Even a seizure is not necessarily a need to panic, but I would act urgently.

The “rules of thumb” that I typically advise is to assess for the presence of ketones in urine (or blood with the special meters and strips) when the glucose is greater than 240 mg/dL [13.3 mmol/L] and, certainly, if the value is greater than 240 mg/dL [13.3 mmol/L] two times in a row when checked about four hours apart. I also suggest that you check for ketones when vomiting. Ketosis often presents with vomiting. But, eating bad tuna fish, heat exhaustion, getting the flu, etc, etc (you get my point) can also lead to vomiting unrelated to diabetes. So, how can you help exclude diabetes as part of the vomiting picture? Why, check for ketones of course.

During your son’s vomiting illness, I might have supposed that his food intake was low, and if received his insulin, this kept his glucose levels and ketones in check. This is part of the “beauty” of insulin glargine (Lantus): there remains a “layer” of background insulin. If you don’t eat as much or if you don’t keep food down, or if you have diarrhea, you likely will not absorb many calories. But, the illness could have led to the production of “stress” hormones such as cortisol and adrenaline, which can maintain the glucose value and prevent some hypoglycemia.

DS