What are the Dangers of Driving with a Hangover?

Most people understand that driving drunk is dangerous and is a common cause of traffic injuries and fatalities. What many people fail to realize is that the effects of drinking and driving do not always wear off after the buzz is over with. Driving while hungover is also dangerous and can lead to serious incidents. You will never see “hungover driving statistics” in any official crash data. There is no way to measure how hungover a person is, but it can still lead to crashes due to a variety of factors.

Why isn’t it safe to drive with a hangover?

The party is over and a person has slept for a few hours. The legal blood alcohol limit for most states is .08%, but a person does not become sober and necessarily ready to drive as soon as their BAC hit .07%. Any alcohol in a person’s system has the ability to impair functioning to a certain extent. Hangovers can also cause:

  • Headaches: It is no secret that many hangovers include a headache. Doctors think that the dehydration caused by drinking alcohol reduces blood flow and oxygen to the brain. When the buzz wears off, the pain receptors in your head are activated. Performing any task with a headache is difficult. Driving with a pounding headache can lead to serious car accidents.
  • Light sensitivity: Many people become sensitive to light when they are hungover. Light sensitivity can make the sun, headlights of vehicles, streetlights, and more unbearable behind the wheel.
  • Motion sickness: Feelings of nausea (along with some vomiting) are not uncommon after heavy drinking. This can lead to motion sickness that lasts for some time, presenting a problem when getting behind the wheel of a vehicle. Simple turns, starting and stopping, and backing up can lead to nausea behind the wheel for hungover drivers. They tell people with upset stomachs and the flu to refrain from driving for a good reason.
  • Those who have been drinking and are hungover are often very tired. Many researchers say that driving while exhausted is even more dangerous than driving while mildly intoxicated (though you should not do either). Even hours of sleep after drinking can seem like only minutes.

There have been several studies used to show the effects of hungover driving. One study in England saw researchers supply drivers with plenty of alcohol the night before a 20-minute driving test on a closed course. The course simulated both rural and urban driving. Researchers found that the drivers displayed an increase in shifting driving positions, slowed reaction times, speed variations, as well as an increase in driving errors.

A study in the Netherlands asked volunteers to drink at least 10 drinks the night before their test and then put them through a one-hour simulated driving routine. These researchers came up with similar findings. In both studies, they waited until drivers registered 0% blood alcohol level, meaning that there was no alcohol left in their systems.

While driving with a hangover is not technically “impaired driving,” it could be argued that the drivers who do so are indeed impaired. While this is not a crime, driving with a hangover can certainly be dangerous and lead to the same results as drunk driving – serious injuries or fatalities.