How long after drinking can I drive?
The answer is it depends on how much alcohol you have drank and the strength of the alcohol consumed.
According to the NHS, on average, it takes approximately 1 hour for a person’s body to break down 1 unit of alcohol.
1 unit of alcohol is equal to 10ml or 8g of pure alcohol (ethanol).
Calculating alcohol units
The number of units in an alcoholic drink can be calculated by multiplying the volume of the alcoholic drink (in ml) by the alcoholic strength by volume (ABV) and dividing the answer by 1000.
To work out the number of units in a standard can of fosters lager you would multiply the amount contained within the can (in this case 440ml) by the alcoholic strength by volume (in this case 4.0% ABV) and divide the result by 1000.
440 x 4 / 1000 = 1.76 units
SO……
- A 440ml can of fosters has 1.76 units of alcohol
- On average a person will break down 1 unit of alcohol per hour
This means the alcohol contained within a 440ml can of fosters will take about 1 hour and 46 minutes to be broken down and eliminated from a person’s body.
A lot longer than most people realise!!
Does everybody eliminate alcohol at the same rate?
Not everyone will break down and eliminate alcohol at the same rate!
The rate at which alcohol is absorbed then broken down and eliminated from an individuals body depends on several factors including:
- Whether they are male or female
- Their age
- Their weight
- Amount of food they have eaten
- Whether or not they have taken any medication
- The rate at which their bodies turn food into energy (their metabolism)
- Whether or not their liver is healthy
There are multiple factors that determine the exact rate an individuals body will break down and eliminate alcohol.
The best way to make sure you do not drive while exceeding the legal limit or while unfit to do so through alcohol is to make sure enough time has passed since you last had an alcoholic drink.
If in doubt. DO NOT DRIVE!!
Common Myths
Cold showers sober you up
FALSE. A cold shower may make you feel fresher and more alert but has no effect what so ever on how fast or slow your internal organs process and eliminate alcohol.
Drinking coffee will sober you up quicker
FALSE. Caffeine which can also be found in tea and energy drinks is a stimulant. It can make you feel more alert and helps combat tiredness but it does not help your body eliminate alcohol any quicker.
A big fry up in the morning will soak up the alcohol
FALSE. The only thing food does is possibly slow down the rate at which alcohol is absorbed into the body. It has no effect at all on the rate at which a body will break down and eliminate alcohol.
A cold shower, a mug of coffee and a big fry up the morning after the night before might make you feel a lot better but will have no effect what so ever on the amount of alcohol in your body or the rate at which your body breaks down and eliminates alcohol.