Drugs and Driving

Many drugs produce effects that impair the ability to drive a vehicle safely. These drugs include both prescribed and over-the-counter medicines. It is difficult to predict the effects of combining alcohol with other drugs. Combining alcohol with other depressant drugs, such as cannabis (marijuana) or heroin, can greatly increase the impairment of a driver. Combining alcohol with stimulant drugs, such as amphetamines or speed, may mask some of the effects that are caused by the stimulants. This makes it difficult for the user to judge how, and to what extent, their driving ability has been impaired.

Increasingly, driving accidents and driving fatalities involve drug use. Driving safely requires attention to many things at once and the ability to react quickly when something unexpected happens.

• A driver requires:
  • mental alertness
  • clear vision
  • physical coordination
  • the ability to react appropriately
    • Impairment of any of these driving abilities can increase the risk of having a crash.
• The dangers of driving after using drugs are due to:
  • taking longer to respond to events or situations
  • possibly choosing an inappropriate response
  • reduced ability to think clearly
  • reduced ability to pay attention (such as not noticing other road users)
  • changes to sight such as blurred vision
  • failing to notice something that would normally have been observed if not impaired by drugs
  • may have an altered view and experience of reality. Their actions and responses may be quite different to what is actually needed
  • may be unaware of the extent to which their driving skills are impaired after using drugs.

Some medicines, both prescribed and over-the-counter, can produce effects that impair the ability to drive safely. It is not always possible to predict whether or not a medicine will affect your driving. You may not notice that a medicine has impaired your ability to drive safely until you are in a driving situation that requires a fast and accurate response in order to avoid a crash.

• Extra care should be taken with medicines used to treat:
  • sleeping difficulties
  • anxiety, depression, and stress
  • pain (such as strong painkillers containing codeine)
  • allergies and hay fever
  • colds and flu
  • arthritis
  • blood pressure
  • epilepsy
  • heart conditions
  • fluid retention
  • nausea
  • stomach problems
  • diabetes
  • some types of infections.
    • Check if your pharmacist can provide you with a Consumer Medication Information Sheet for each medicine that you use. A person who uses medicines may think they can alter their driving to counteract any reductions in their driving ability due to the effects of the medicine.
      

When starting a new medicine that can impair your driving ability, allow several days for the body to adjust to the medicine before deciding if it is safe to drive. If worrying side effects are experienced, your doctor may be able to recommend another medicine or therapy. Always seek your doctor’s advice before stopping or decreasing the use of a medicine.

• To reduce the risk of a crash:
  • avoid combining medicines with other medicines or other drugs, including alcohol
  • keep to the prescribed doses and intervals. Some medicines may enhance a driver’s ability to drive safely by reducing stress, anxiety, or other conditions (such as epilepsy) that, if left untreated, may make driving dangerous. Avoid driving if you miss a dose of a medicine that enhances your ability to drive safely. Resume driving only after you are sure that you can do so safely.
  • only use your own medicines
  • ensure that your doctor and/or pharmacist know all the medicines you are using, both prescribed and over-the-counter. Ask if it is safe for you to drive
  • if driving can not be avoided then stick to familiar routes, daytime driving, and short trips.
  • always check with your doctor or pharmacist whether a medicine can affect your driving.

Warning Labels
Before driving, check with your doctor or pharmacist if a medicine has one of the following labels:

“This medicine may cause drowsiness and may increase the effects of alcohol. If affected do not drive a motor vehicle or operate machinery”

OR

“This medicine may affect mental alertness and/or coordination. If affected, do not drive a motor vehicle or operate machinery”