Which medicines can affect my driving?

Some medicines have side effects that can affect your ability to drive safely. It's illegal to drive under the influence of drugs. This means all drugs, whether they are:

• over-the-counter medicines
• complementary medicines
• prescribed medicines from your doctor
• illicit drugs

How will medicines affect my driving?

To drive safely, you need to be able to see, think and react properly.

Some medicines, can affect these skills. If you are taking these medicines, it may not be safe to drive.

The risks of being affected by your medicines are greater if you are:

• taking more than one medicine
• drink alcohol while you are taking medicines

How can my medicines affect me?

Some common side effects of medicines that can affect your driving include:

• feeling drowsy or tired
• feeling dizzy, faint or nauseous
• blurred or double vision
• shakiness or unsteadiness
• confusion and being less alert
• not being able to concentrate properly
• not being able to judge distance or speed properly
• reacting more slowly
• muscle weakness or being less coordinated
• anxiety or other changes to your mood

Some medicines can affect your driving to a great extent. The effect can be the same as driving when you are over the legal limit for alcohol.

If you think your medicine is affecting your driving, do not stop taking the medicine. You should stop driving and talk to your doctor. There might be other medications you can take.

Which medicines could affect my driving?

Some examples of medicines that might impair your driving are:

• sleeping pills and medicines for anxiety (including complementary medicines)
• epilepsy medicine
• some antidepressants — used for nerve pain, migraines, bladder problems and depression
• antipsychotics — used for conditions like schizophrenia and bipolar disorder
• some antihistamines — used for allergies, colds and flu
• opioids — used for pain relief
• some cold and flu preparations
• some medicines for blood pressure, nausea, inflammation or fungal infections
• diet pills
• medicinal cannabis that contains delta-9-tetrahydrocannabinol (THC)

Cannabidiol does not contain THC but it can also cause you to feel sleepy or tired. It could cause low blood pressure. Talk to your doctor about whether it is safe to drive.

Not everyone's driving will be affected by these medicines. It depends on:

• how your body adapts to the medicine
• how long you take it before you drive
• what other medicines you are taking

Your sickness or your medical condition can also be a factor in any effect on driving.

Safe medicines

Some medicines can make you a safer driver. These medicines are used to treat conditions that would affect your driving, such as:

• diabetes
• epilepsy
• heart disease

What should I do when I start a new medicine?

Ask your doctor or pharmacist whether it is safe to drive. You should also:

• Always read and follow the instructions on the medicine's warning label.
• Do not take more than the prescribed dose of the medicine.
• Do not drink alcohol or take other drugs while you are taking medicines.
• Remember that the medicine might affect your driving more when you first start taking it. Over time, you may get used to it and experience fewer side effects.

Do not drive if you have missed a dose of medicine that you need to control symptoms that could affect your driving. Arrange another form of transport, such as public transport or a taxi.

Do not stop taking your medicine or change the dose without talking to your doctor first.

Tips for starting a new medicine

When you are taking a new medicine, it's a good idea to see what effect the medicine has. You should not drive until you are sure that the medicine will not affect your ability to drive.

Some medicines can last in your system for a long time. You might still be affected by a medicine the next day.

If you've taken a sleeping tablet you might still be drowsy the next morning. This is similar to having a 'hangover' from too much alcohol the night before.

You need to be sure that you can drive safely after taking your medicines.

Prescription medicines and driving laws

Driving under the influence of drugs can carry heavy fines.

If you have a medical condition that could affect your driving, you will need to tell your state or territory licensing authority. You may need to give them a medical report from a doctor stating that you are fit to drive.

If you take medicines for diabetes, you should always check your blood glucose level before driving to make sure it's not too low — it should be 5mmol/L or more.

Resources and support

State and territory governments are in charge of road rules and road safety. You can find specific information for your state or territory at:

• Australian Capital Territory: Access Canberra 13 22 81
• New South Wales: Transport for NSW 13 22 13
• Northern Territory: Northern Territory Government information and services
• Queensland: Queensland Government 13 74 68
• South Australia: Department for Infrastructure and Transport
• Tasmania: Transport Tasmania 1300 135 513
• Victoria: VicRoads 13 11 71
• Western Australia: Main Roads 138 138

You can also call the healthdirect helpline on 1800 022 222 (known as NURSE-ON-CALL in Victoria). A registered nurse is available to speak with 24 hours a day, 7 days a week.