Alcohol, Drugs, Fatigue and Fitness to Drive
Fitness to drive is a legal and safety issue. Alcohol and drugs (including some medicines) slow reactions, impair judgement and reduce coordination; they raise the risk of collision sharply. The safe and lawful position is not to drive after drinking alcohol or taking impairing substances. If you are taking medication, read the label and ask a pharmacist whether it affects driving.
Fatigue is a serious hazard that drivers underestimate. Warning signs include yawning, heavy eyelids, difficulty concentrating, drifting and missing signs. The remedy is to stop in a safe place and rest; opening a window, turning up music or drinking coffee are only short-term measures and do not replace sleep. Plan long journeys with breaks and avoid driving during hours when you would normally be asleep.
Illness and eyesight also matter: you must be fit to drive, and if you need glasses or contact lenses to meet the eyesight requirement, you must wear them while driving. Emotional stress and distraction (including mobile phones) impair fitness just as surely as alcohol.
Traps: questions may suggest a 'cure' for tiredness such as fresh air or loud music; the correct answer is to stop and rest. Another trap is assuming a small amount of alcohol is safe; the safe answer is none before driving.
Rule of thumb: if you feel sleepy, stop and rest; if you have been drinking, do not drive. Worked example: you feel drowsy on a long trip; pull into a safe stopping place, rest, and continue only when alert.