Morning-after drivers are a particular focus for the police this year under its Christmas drive-drive campaign. A total of 280 people lost their lives in the UK during 2011 as a direct result of drink or drug driving, despite the well-documented dangers associated with getting behind the wheel while under the influence of drink or drugs. 

Previous research amongst the AA/Populus panel of 11,388 drivers found that one third (34%) felt they could often be over the limit the morning after and almost one half (46%) thought they might be occasionally be over the limit the following day.

Edmund King, AA president, said: 'Too many drivers are caught out by being over the limit the morning after the night before. We don’t want the morning after to end in mourning disasters so are advising drivers to think carefully before driving after a night out.

'It is difficult to work out whether there is still alcohol in the system the following day. One unit of alcohol takes about one hour to get out of the system. However this is not a precise science as it depends on size, gender, whether you have eaten, state of your liver, metabolism and even mood. There is also confusion over units of alcohol due to varying strengths of beers and wines and different sizes of glasses.

'If drivers are unsure the following day the self-test breathalyser should give an indication of whether alcohol is still present. However, our advice remains, if in doubt, don’t drive.'