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How long before you drive should you test your blood?

Clementine68

Member
Messages
19
Location
Rossendale
Type of diabetes
Type 1
Treatment type
Insulin
I have always wondered but not been able to find anything. How long before you drive should you test your blood ie 10 minutes, 20 minutes. In the morning I test my blood before having breakfast and unless is below 4 I do not test it again before I drive about 45 mins later. I don't really want to be testing twice in an hour, but what do other people think.
 
To drive in the UK you need to test your blood sugars by finger prick and achieve a reading of above 5mmol every two hours. Once two hours has passed, you will need to test again.

If you are testing 45 mins before you drive and your commute is less than 75 mins then you are fine as you are. No need to prick twice. Just remember if you are below 4 you legally can't drive for 45 mins anyway.
 
Depends on the journey. Like you, I will test in a morning before breakfast and if that result is >=5.0 I'll use that for my commute of about 25 minutes. If it's below I will retest before driving to make sure I've headed in the right direction. On longer journeys especially I will test right before driving.

I don't get behind the wheel if <5.0 as per the guidelines and if I'm due to drive after a hypo I wait the 45 minutes after rising above 5.0 before retesting and making the journey.
 
I test immediately before driving because it can drop low so very quickly, especially the nearer to 4 it is. The law says if it is below 4 (when tested before driving) then have something to eat. I have heard people say you cannot drive with it under 5 but when you read the actual information it doesn't say don't drive if under 5 but 'have something to eat'. For safety reasons I personally would not test 45 minutes prior to driving as I think it could be a whole different story 45 mins later and I would not want to risk an accident. Also, it says to test every two hours whilst driving but as you say it does not say how long prior to driving you should do the test.
 
You should not be driving if you have not tested in the preceding two hours. Therefore it clearly depends on how long you will be driving for. (As you may not be able to stop to test due to traffic etc, I think it is better to plan the testing, so you are never driving more than 90 minutes after a test.)
 
Thank you for the replies that puts my mind at rest.

I am aware that if a test is <4 that once stable you are supposed to wait 45 mins before driving but do wonder how many people actually do?
 
yes I also test every two hours especially if towing the caravan any where
 
I too use my breakfast test as my drive test in the morning for my work commute, I also test before I leave work, so I can fix any issues before I get back to the car. Any other time I'd test just before driving.

But I was wondering about the wording of the rule (which I don't have in front of me right now) and this is only for arguments sake; so you could test 1hr 59mins before setting off, technically you're within the law, correct? so does it say you then have to test every 2 hrs of driving. So your next test could well be 3hr 59mins after your first test and still be within the law?!

And that m'lord is why the defendant believes he has nothing to answer for..............

 
Remember the law on dangerous driving say “you must not drive in a way that you know is dangerous, or should have know is dangerous”. These guild lines are what a court will use to help define “know is dangerous”, and you have to convince 12 people you have kept to them in a reasonable way. (For example, if you often get low after the gym, you will know it is dangerous to drive without testing, even if it is less then 2hr from your last test.)

Other then HGV drivers, no one will check what testing you are doing until they are trying to put you in jail.....
 
Hi, I keep a test kit in the car (got into the habit when I was on insulin)I made it part of my car routine to not only put on my glasses, strap in etc but to do a fpt just before I set off, every time I would stop I would also check before setting off.

Sounds ott and ocd but driving with my kids in the car... better safe than sorry.
 
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