A new study suggests that climbing behind the wheel with a raging hangover could be just as dangerous as attempting to drive while over the legal drink-drive limit.
Researchers from the University of the West of England ran a driving simulation that replicated both town and rural driving conditions, then asked revellers who had been drinking the night before to see how they fared.
"Things like their speed of reaction were slowed down. The variability in the way they drive was more erratic," said Chris Alford, who led the study.
"You could say their driving was as if they were over the legal limit of alcohol, but of course they didn't have that alcohol on board any more."
The test was designed to make motorists aware of the hidden dangers of driving after a heavy night of drinking. The risk is not simply being caught over the limit but the fact that reaction times are slowed and mistakes are more likely to be made when driving the morning after a big night out.
A similar study at Utrecht University in the Netherlands asked volunteers to take part in a simulated one-hour motorway driving test after consuming around ten alcoholic drinks the night before.
Despite the drivers' tested blood-alcohol level returning to zero, their standard of driving was similar to being over the drink-drive limit.