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Washington driving lesson · The Driver

Alcohol, cannabis, medications, and polydrug use

A 3-minute lesson from the Washington course. Read the rules and examples, follow the handbook page references, and check your understanding before you move on.

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Read time
3 minutes
Course unit
The Driver
Checkpoint questions
6
Source pages
72, 73, 74, 75

Impaired driving happens when anything makes it hard to think straight, respond quickly, or control your car. Alcohol is the usual suspect, but cannabis, prescription and over-the-counter medicines, and mixing substances all count, and the penalties are tough.

Know the rule

Penalties for driving under the influence of alcohol or drugs include expensive fines, higher insurance rates, license suspension or withdrawal, and even jail.

Handbook p. 72 ↗

Know the rule

Alcohol is the most common impairing substance in impaired driving crashes. Watch for impaired drivers and give them lots of room.

Handbook p. 72 ↗

Alcohol can cause:

  • Relaxation and drowsiness
  • Blurry vision or limited eyesight
  • Slower reactions and less concentration and scanning
  • Difficulty understanding what's happening
  • Trouble doing several tasks at once, like staying in a lane while avoiding traffic
  • Inability to obey the rules of the road
  • Overconfidence that leads to risky driving
Handbook p. 72 ↗

Please:

  • Don't drive any vehicle after consuming impairing substances
  • Don't ride with a driver who has had any kind or amount of impairing substance
  • Don't let friends or family drive after drinking or using drugs
  • Plan for a sober driver
Handbook p. 73 ↗

Know the rule

Recreational cannabis is legal for those 21 or over, but driving after consuming any cannabis is illegal for all ages. There is no safe amount of cannabis for driving.

Handbook p. 73 ↗

Cannabis can cause:

  • Reduced attention, reaction time, and coordination
  • Decreased car handling
  • Inability to judge distances
  • Increased drowsiness
  • Loss of motor coordination
  • Impaired mental and physical functions
Handbook p. 73 ↗

Know the rule

A legal drug is not necessarily safe for driving. Impaired driving is criminal whether the drug is prescribed, over-the-counter, bought in a retail store, or illicit.

Handbook p. 74 ↗

Know the rule

Over-the-counter drugs for headaches, colds, or allergies can make you drowsy. Prescription drugs can affect reflexes, judgment, vision, and alertness.

Handbook p. 74 ↗

Know the rule

Don't drive after starting a prescription for the first time, a new medicine, or a higher dose until you know how it affects your judgment, coordination, and reaction time.

Handbook p. 74 ↗

Know the rule

Read warning labels: "operating heavy machinery" includes driving. Some medicines cause severe impairment when combined with another medicine or alcohol.

Handbook p. 74 ↗

Polydrug use

Mixing or taking more than one type of drug, which can produce effects greater than any drug alone. It's the most common impairment involved in fatal crashes.

Handbook p. 75 ↗

Put it into practice

You take a new allergy pill whose label warns against operating heavy machinery, then feel drowsy. Don't drive until you know how the medicine affects you. The warning covers driving.

Check your understanding

Read the question, decide on an answer, then open it to check the explanation. These are Roadwise study questions based on the source handbook.

Recreational cannabis is legal for adults 21 and over. At what age is it legal to drive after consuming cannabis?
  1. Any age, with a medical card
  2. At no age; it is illegal for all drivers
  3. 21 and older
  4. 18 and older

Answer: At no age; it is illegal for all drivers

Recreational cannabis use is legal for adults 21+, but driving after using any cannabis is illegal for all ages.

Handbook p. 73 ↗
You just started a brand-new prescription medication. What's the safest approach before driving?
  1. Wait until you know how it affects your judgment and coordination
  2. Drive normally since it's prescribed
  3. Only avoid driving at night
  4. Take half the dose before driving

Answer: Wait until you know how it affects your judgment and coordination

Don't drive after starting a new medication or higher dose until you know how it affects you.

Handbook p. 74 ↗
Which type of impairment is most commonly involved in fatal crashes, according to the handbook?
  1. Alcohol alone
  2. Cannabis alone
  3. Fatigue alone
  4. Polydrug use

Answer: Polydrug use

Polydrug use, mixing more than one substance, is the most common impairment involved in fatal crashes.

Handbook p. 75 ↗
Just because a drug is legal or over-the-counter doesn't mean it's safe to use while driving.
  1. True
  2. False

Answer: True

Legal and over-the-counter drugs can still impair your ability to drive safely.

Handbook p. 74 ↗
There is a safe amount of cannabis you can consume before driving, as long as you feel fine.
  1. True
  2. False

Answer: False

The handbook states there is no safe amount of cannabis for driving.

Handbook p. 73 ↗
Which effect does alcohol have on drivers, according to the handbook?
  1. Greater caution and less risk-taking
  2. Reduced reaction times and ability to scan the environment
  3. Improved multitasking ability
  4. Sharper concentration

Answer: Reduced reaction times and ability to scan the environment

Alcohol reduces reaction times, concentration, and the ability to scan the environment.

Handbook p. 72 ↗
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