stomach pain

Hi, I just want to clarify, do you mean bmi (body mass index)? or do you mean his bg (blood glucose) being up and down for weeks? A tummy ache could be anything but two things if it was my child that I'd want to check is that he isn't unwell due to high readings (I'm not sure if you meant his bg is up), if he's been having high readings regularly then I'd want to check for ketones and rule out risk of developing ketoacidosis due to poorly controlled blood glucose, a tummy ache can be a symptom. The other thing I'd do is have a chat with his consultant and ask for a blood test to rule out coeliac. Type 1 diabetics are more at risk of developing coeliac and a symptom of this can be tummy aches and discomfort. Another symptom of coeliac in type 1 diabetics is unstable blood glucose readings. Does he have constipation at all? That could also cause discomfort and if his bg is up and down it could be affecting his tummy in that way. High bg readings can mean that more water is passed as urine leaving less in the bowel resulting in constipation, your gp may be able to prescribe something.