If I’ve had an absolute skinful the last thing I do is drive in the morning. Its not rocketscience.

Had a bit of an all dayer in Perth a few weeks ago, finished drinking about Midnight, would of had anywhere between 32-40 units in my system by the time I’d finished, so I shouldn’t really have been driving for at least 27 hours?? but anywhere up to a day and a half if its true that your body doesn’t start processing the alcohol until after your last drink..

If he was twice the limit at 5 in the evening, how lagging must he have been when he drove in?!?!

“we’ve all done it”

I haven’t.

We’ve all done what?

Drive knowing you are definitely over the limit the next morning? If you hit a cyclist and say it was the cyclists fault, can you imagine?

The liver starts metabolising alcohol almost as soon as it hits the bloodstream. It’s a poison, your body is well-designed to start getting rid as soon as it is detected.

8 pints is a breeze on a big night out surely?

I used to drink a lot when I was younger (or I thought I did) but I’d never manage 8 pints. After 6 I’d be unconcious.

You break down approx one unit per hour but doesn’t start until an hour after you finish your last drink.

Sounds a bit of a stretch?

Say I go on the beer on all day session from 2-12 that 10 hours drinking, could probably sink about 12-15 pints in that time, call it 12 to be on the conservative side.

so 1am, it starts breaking down 12pint x 2.5 units = 30 hours, so you can’t start driving till 9am then following day?

if that’s the case there are loads of people drink driving all the time.. i’d guess it breaks down in more of a curve rather than a linear fashion.

Personally I don’t have a license anyhow, so not something I’ve ever had to worry about. Though i didn’t crash into a parked car one morning on my bike, no alcohol involved the previous night either, tbh I think i’m better off without! 😀

Having attended a drink driving course (yes, I know), I can confirm that about 2/3 of the people also attending had been caught the “morning after”. It is a very real concern, believe me.

Seosamh – your maths is pretty spot on. The difference is that people who regularly binge drink to that degree often develop greater alcohol tolerance which means you may be less obviously impaired than someone (like me) who is getting pissed after two pints and seriously screwed driving-wise with even that amount of alcohol in my bloodstream.

But you’ll still be over the limit, quite likely affecting your driving skill, even if you don’t notice it yourself, and risking a ban.

if its true that your body doesn’t start processing the alcohol until after your last drink..

It’s not. If it was you wouldn’t be able to do an “all dayer”. You would pass out or go into a coma.

Blowing twice over the limit at 5pm the next day means he must have had a top up during the day.

The 1 unit an hour is a very conservative estimate and everyone is different. I remember playing with “official” and calibrated breathalysers and I was surprised how hungover you could feel and how low you would blow.

Would a member of the public 5 times over the limit get a 2 month ban

You will struggle to find anyone convicted of being 5 times over the drink driving limit. By most standards, a healthy person with this level of blood alcohol will either be comatose or dead. A chronic alcoholic might be sleepy but unlikely to drive.

If your friend really was over the limit at 5PM then there are a couple of explanations;

1) He is not telling the truth. The body removes approximately 1 unit of alcohol per hour. If he is a heavy drinker this may increase slightly. A pint of beer is about 2.5 units (and if downed in one will just take a 70 kg adult to the limit).

2) He has liver disease and is incapable of metabolizing alcohol effectively. This might show by intoxication.

Alcohol elimination is very predictable. It is one of the few drugs that saturate metabolic pathways – hence back-extrapolation is quite simple. To avoid intoxication – even over long sessions, drink no more than one unit per hour. Most people are incapable of doing this 😉

I have an alcohol demonstration for the kids I lecture; Half fill six sherry glasses with juice. That is the volume of alcohol in a pint of beer or large glass of wine. Now pour one into a measuring jug. Scoop out 10ml (tablespoon) due to metabolism for the first hour. Repeat ad/to nausea. You’ll see how easy it is to accumulate alcohol in the body and how slow it is removed! There is a very good relationship betweem blood alcohol concentration and functional capacity which I like to show on the side of the jug for concentration.

I got clipped by a drink driver in a van a few years back, so I have no sympathy.

There are no excuses for drink driving any time of the day or night, period!

martinhutch

fair enough, quite surprised it takes so long though!

So if I was to start drinking wine at 7pm and drank a bottle through the evening till 10:30pm, which I assume is around 10 units …. would this have worked it’s way out of the body for about 7am ?

RobinL – difficult to be certain as everybody is different. However, I think it’s reasonable to say that if you are a regular drinker in good health, the alcohol from the wine would be processed by 5am.

It’s a linear process; 10 units input. 2.5 units out during the meal, 1.5 from 10:30 till midnight and another 7 from midnight till 7am. So yes you should be OK. The error in the calculation will be about a unit or two based on your body weight and drinking history (liver capacity).

The drink driving blood alcohol driving limit is roughly two units taken as a bolus (downed in one) and instantly absorbed.

So how do people avoid this, I happily stay over at a friends or in a Hotel for a night if away from home for a night out, but then drive home the next day. I wait till after 12 pretty much every time, so I assume there are still chances I risk being over the limit.

I hate drink driving, so aside from buying a home tester (which may/maynot be accurate) what can I do to ensure I’m not over the limit – aside from drink less or wait longer?

Work backwards from what you have drunk. I drink very sparingly, so 4x the drink driving limit would see me passing out! That is about 10-12 units of alcohol. If I was that drunk it would require 12 hours to eliminate.

If you are a regular drinker, then you will be able to perform tasks with higher intoxication – much higher if you are an alcoholic. Metabolism will help, but 12 hours is a reasonable rule of thumb to elimiate 12 units of alcohol, and 12 units in the body at once will make most people pretty squiffy.

I hate drink driving, so aside from buying a home tester (which may/maynot be accurate) what can I do to ensure I’m not over the limit – aside from drink less or wait longer?

Think you’ve already answered your own question there.

I’m glad I started this thread, has been a real eye opener.

I started it because I didn’t believe him. General consensus here seems to be either that he was lying and had been drinking during the day or that he must have put away a monster session the night before that would see him a likely having a drink problem.

Either way, he was over the limit , that is the only thing not in dispute! I’m glad I am not sharing the roads with him for the next 13 months.

Half fill six sherry glasses with juice. That is the volume of alcohol in a pint of beer or large glass of wine. Now pour one into a measuring jug. Scoop out 10ml (tablespoon) due to metabolism for the first hour. Repeat ad/to nausea. You’ll see how easy it is to accumulate alcohol in the body and how slow it is removed!

TiRed – This makes no sense to me?
Why half fill six sherry glasses?
A sherry glass is normally about 120ml which would be 60ml of alcohol.
A pint is 568ml, so by your reckoning a pint is normally about 10.6%, drink in Belgian bars a lot do you?
Working on beer at 3.5%, that would make about 20ml in a pint, or 2 units.
At 10ml that is an unit per hour. Which is what the guidance suggests.
Your biology might be good but your maths aren’t. 🙂

I think part of the next morning problem is the accelerating drinking at the end of night. Start on beer, finish on spirits… a double for the road.

I’ve been sat in taxis on the way home feeling myself getting drunker from this effect. It’s even worse if you are at a party or someone’s house so no-one is being sensible about measures.

Ever had the waking up after a big sess and feeling good – only to realise that you are still (a) a bit p*****d and (b) for the hangover to kick in a couple of hours later. I am really careful about driving after a big night. Fortunately mrs OD is not a big drinker.

On the amount you can drink in a night, when I was younger, fitter (and played rugby) I could do 12+ pints of (not especially strong 1980s)bitter after a match – I think I would require hospitalisation now!

I don’t think 8 pints is over the top for a big night out, especially if you make a day of it. For a Thursday night trip to the pub I would do 5 or 6 pints over an evening and I am not a massive drinker.

I do like the idea that your body gets the signal that you have had the last drink so it can start processing booze 😆

I don’t think 800 pints is over the top for a big night out, especially if you make a day of it. For a Thursday night trip to the pub I would do 56 pints over an evening and I am not a massive drinker.

I do like the idea that your body gets the signal that you have had the last drink so it can start processing booze

I’m pretty careful to be fair and I do like a beer! Can happily have 6 pints on a sun afternoon but we’re always finished early (8 ish) and have some dinner. That must also factor in or not?

So this tolerance that your body builds up, is that actually your liver being more screwed?

I’m trying to feelgood(tm) my low beer tolerance. 😉

Easy enough to believe if it had been 9am. But 5pm? What was he doing for the rest of the day?

Drinking alcoholic booze by the sounds of it.

I do like the idea that your body gets the signal that you have had the last drink so it can start processing booze

kebab

So this tolerance that your body builds up, is that actually your liver being more screwed?

I’m trying to feelgood(tm) my low beer tolerance.

I thought it was the presence of the correct enzymes (alcohol dehydrogenase?) building up. In the same way you train your body to get fitter you can build up tollerances to things as your body reacts to repeated onslaughts.

He is trying to gather sympathy

This is a good reason for him not to be given his licence back.

Shame he’s not going around saying ‘thank God I didn’t kill anyone, what an idiot I’ve been’

We need a maturity test as part of the process to get a licence

I thought it was the presence of the correct enzymes (alcohol dehydrogenase?) building up. In the same way you train your body to get fitter you can build up tollerances to things as your body reacts to repeated onslaughts

Those enzyme systems aren’t really inducible by repeated drinking

The “general” P450 oxidase system metabolises a minority of the alcohol you drink but it can get “better” (be induced) with repeated exposure, so that the minority it deals with is larger. Trouble is, it’s believed that this increases the toxicity of alcohol (as well as other things like paracetamol)

(Oh, tolerance is not mainly about being better at getting rid of the stuff – your brain gets better at dealing with its presence)

Why half fill six sherry glasses?

OK, 1 unit is 10 ml (8g), so 25 ml is the volume required for a pint of beer. Half a small sherry glass. How’s that?