Notes

When you drive, your hands, eyes and feet control the vehicle, and your brain controls your hands, eyes and feet. To drive safely, you need to be alert, aware and able to make quick decisions in response to a rapidly changing environment.
Alcohol and other drugs alter the normal function of the brain and body, and interfere with even the most skilled and experienced driver’s ability to drive safely. While different drugs can have different effects on driving, any drug that slows you down, speeds you up or changes the way you see things can affect your driving—too often with tragic consequences.
Alcohol and other depressant drugs
Alcohol blunts alertness and reduces motor co-ordination. People who drive after using alcohol can’t react as quickly when they need to. Their vision is affected, and may be blurred or doubled. Alcohol alters depth perception, making it hard to tell whether other vehicles, pedestrians or objects are close or far away. And because alcohol affects judgment, people who drive after drinking may feel overconfident and not recognize that their driving skills are reduced. Their driving is more likely to be careless or reckless—weaving, speeding, driving off the road and, too often, crashing.