Research by road safety charity Brake found that one in five drivers admit to driving the morning after they drank a lot the night before.[1]
Furthermore, a Freedom of Information request from insurers LV found that arrests for drink driving between 06:00 and 08:00 rose from 350 in 2011 to 363 in 2012 - an increase of 4%.[2]
While far fewer people are taking the risk of drink-driving above the legal limit at night,[3] people are getting into their cars in the morning, without realising they could still be over the legal limit to drive. Just because you’ve been to sleep, it doesn’t mean you’re no longer affected by alcohol.
“Many drivers who would not consider driving after a night in the pub fail to recognise the influence of alcohol on their body the next day, or simply choose to ignore its effects,” says Alice Granville, policy and research analyst from the Institute of Advanced Motoring. “Drivers need to take responsibility and use alternative means of transport after a heavy night drinking.”
In England, Wales and Northern Ireland, the alcohol limit for drivers is 80 milligrammes of alcohol per 100 millilitres of blood, 35 micrograms per 100 millilitres of breath, or 107 milligrammes per 100 millilitres of urine.
In most other European countries, the limit is less, usually 50 milligrammes per 100 millilitres of blood.[4]
The alcohol limit for drivers in Scotland has been different to the rest of the UK since 2014. The limit is 50 milligrammes of alcohol per 100 millilitres of blood, 22 micrograms of alcohol per 100 millilitres of breath, and 67 milligrammes per 100 millilitres of urine.[5]
For more information about the drink driving limit in Scotland visit the Don’t Risk It campaign site.
Whether it’s okay to drive the next morning depends on how much you’ve drunk – and if you’ve left enough time for your system to get rid of the alcohol. “The amount of alcohol in your bloodstream depends on three things,” says Dr Paul Wallace, Drinkaware's Chief Medical Adviser. “The amount you take in, over what period of time and the speed at which your body gets rid of it.”
In general, alcohol is removed from the blood at the rate of about one unit an hour. But this varies from person to person. It can depend on your size and gender, as men tend to process alcohol quicker than women; how much food you’ve eaten; the state of your liver, and your metabolism (how quickly or slowly your body turns food into energy). The best advice, if you don't want to put yourself and others in danger, and break the law, is to avoid alcohol altogether the night before you have to drive.
There’s a mixture of mechanisms at work when your body processes alcohol, mainly enzymes in your liver doing their job of breaking down alcohol. This process can take longer if your liver is damaged or not working normally.
There’s nothing you can do to speed up the rate alcohol leaves your system.
“Having a cup of coffee or a cold shower won’t do anything at all to get rid of the alcohol,” says Dr Wallace. “They may make you feel slightly different, but they haven’t eliminated the alcohol in any way.”
If you’re thinking about driving the morning after you’ve been drinking, it’s best to consider how much you had, and how late into the night it was before you finished your last drink.
Remember, the strength of different drinks can vary greatly. Some ales for example are 3.5%, but stronger continental lagers can be 5% ABV, or even 6%. White wines vary from around 8% to 15%.
There’s no fail-safe way to guarantee all the alcohol you’ve drunk has left your system, so it’s important not to take risks. As Dr Wallace points out, when you’re under the influence of alcohol at any level, the skills you need when you’re driving, such as hand eye coordination, are impaired to some extent. You’re more likely to have an accident.
“As well as the legal reasons, there are common sense reasons: you don’t want to be out on the road and putting yourself and others at risk.”
