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How do drugs, tiredness and other factors impair a driver, and how can they be avoided?

The effects of illegal and prescription/over-the-counter drugs, fatigue, illness and distraction on driving, and how each impairment can be avoided.

A CCEA GCSE Motor Vehicle and Road User Studies answer on how illegal and medicinal drugs, fatigue, illness and distraction impair driving, and the steps a driver can take to avoid each.

Generated by Claude Opus 4.89 min answer

Reviewed by: AI editorial process; not yet individually human-reviewed

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  1. What this dot point is asking
  2. The answer
  3. Examples in context
  4. Try this

What this dot point is asking

CCEA wants you to explain how drugs (illegal and medicinal), fatigue, illness and distraction impair driving, and what a driver can do to avoid each. These join alcohol as the main causes of impaired driving, and the exam often asks for both the effects and the prevention.

The answer

Drugs

Both illegal and legal drugs can impair driving.

  • Illegal drugs can slow or speed up reactions, distort the sense of speed and distance, cause drowsiness or over-excitement, blur vision, reduce concentration and increase risk-taking. Driving with specified controlled drugs above set limits is a separate offence from drink-driving.
  • Prescription and over-the-counter medicines - some hay-fever tablets, cough and cold medicines, strong painkillers and sleeping tablets - can cause drowsiness, slowed reactions and reduced concentration.

Fatigue (tiredness)

Fatigue is a major and under-rated cause of serious collisions, especially on monotonous roads and at night.

Effects of fatigue include slower reactions, poor concentration and lapses of attention, microsleeps (briefly nodding off), impaired judgement and drifting out of lane.

Illness and distraction

  • Illness - colds, flu, pain or conditions that affect alertness can impair driving; serious medical conditions (for example epilepsy or poor eyesight) may legally have to be declared to the licensing authority.
  • Distraction - using a hand-held mobile phone, eating, loud music, adjusting controls or attending to passengers all reduce attention. Using a hand-held phone while driving is an offence.
  • Eyesight - a driver must be able to read a number plate at the required distance; failing the basic eyesight standard means you are not fit to drive.

Worked example: a medicine before a drive

Examples in context

Example 1. A microsleep on the motorway. A tired driver nods off for two seconds at 70 mph and travels over 60 metres with no control - which is why planned breaks matter.

Example 2. The phone glance. Looking at a phone for two seconds means driving "blind" for the whole distance covered, which is why hand-held phone use is both dangerous and an offence.

Try this

Q1. Name one effect of fatigue on a driver. [1 mark]

  • Cue. Any one of: slow reactions, poor concentration, microsleeps, drifting out of lane.

Q2. What should a driver do before taking a new medicine and driving? [2 marks]

  • Cue. Read the label/leaflet and ask a pharmacist or doctor; do not drive if warned.

Q3. Give one common in-car distraction that reduces a driver's attention. [1 mark]

  • Cue. Any one of: hand-held mobile phone, eating, loud music, adjusting controls.

Exam-style practice questions

Practice questions written in the style of CCEA exam questions on this dot point, with worked answer explainers. The year tag is the paper they imitate, not the source.

CCEA style4 marksDrugs can impair a driver. Explain how (a) illegal drugs and (b) some prescription or over-the-counter medicines can affect driving, and state what a driver should do about medicines.
Show worked answer →

(a) Illegal drugs can cause slowed or speeded reactions, distorted perception of speed and distance, poor concentration, drowsiness or over-excitement, blurred vision and risk-taking - all of which make safe control of the vehicle impossible. Driving with certain drugs in the body above set limits is a specific offence.

(b) Prescription or over-the-counter medicines (for example some hay-fever tablets, cough medicines, painkillers or sleeping tablets) can cause drowsiness, slowed reactions and reduced concentration.

A driver should read the label/patient leaflet, ask the pharmacist or doctor whether a medicine affects driving, and not drive if it warns against it. Markers reward effects for each plus the advice to check the label/ask a professional and not drive if warned.

CCEA style4 marksTiredness (fatigue) is a major cause of collisions. Describe two effects of fatigue on a driver and two things a driver can do to avoid driving while tired.
Show worked answer →

Effects (any two): slower reactions; poor concentration and lapses in attention; microsleeps (briefly falling asleep at the wheel); impaired judgement; drifting out of lane.

Avoiding it (any two): plan rest stops on long journeys (a break of at least 15 minutes about every two hours); get enough sleep before setting out; avoid driving at times you would normally be asleep (late night/early morning); if drowsy, stop in a safe place and take a short nap and a caffeinated drink; share the driving where possible.

Markers reward two genuine effects and two genuine prevention measures.

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