I fell asleep before I gave myself an insulin injection last night so my fasting glucose this morning was 10.6. I have taken the insulin 3 hours ago now but am wondering how high is too high to drive? I do not get lows below 4.0 in part because I fear them and eat enough to keep my blood glucose higher. I have read many postings here and all seem to deal with lows but surely there is a cutoff for highs as well? I read the UK regulation for insulin users to test at least twice a day and not have more than 1 hypo in the last 12 (months?). I meet that regulation. I am in the USA and had to declare my diabetes and insulin use here but am just required to carry candy in the glove box. It's sort of a nuisance because my mother who has dementia remembers where the candy is and continually takes it out and eats it. I would not drive with blurry vision which I get when my BG is really high but what actually is the cut off?