How much should BG rise or fall after a carbohydrate free meal?

Hi
I've forgotten how much blood glucose should rise or fall after a carb free meal when checking BI dosage. I tend to be more active during the spring and early summer (injecting 6 units of Levemir night and morning) and think it's time to up the BI dose to 7 as my blood sugars are getting higher but can't remember the maximum variations - and can't find the information in my DAFNE course booklet

Peta

I've found the suggested variation (< 1.5) over a series of carb-free maeals so don't think I need a reply- unless a health professional thinks I've got it wrong