Driving and medicines

Some prescription and over-the-counter (OTC) medicines can affect you in a way that makes it unsafe for you to drive. In New Zealand it is against the law to drive while impaired.

On this page, you can find the following information:

How can medicines affect driving?
Which medicines are most likely to affect driving?
How long should I avoid driving for?
Alcohol, medicines and driving
Older adults, medicines and driving

How to make sure you are safe to drive
If you are taking medicines and thinking of driving: know how your medicines can affect you by asking your doctor or pharmacist check how you feel before and while you drive stop driving or don’t start driving if you feel impaired. ✔ Ask your doctor or pharmacist if the medicine you are given affects driving and whether it is safe for you to drive. ✔ Read your medicine labels to see if it can affect your driving. ✔ If you feel that the medicine you are taking is affecting your driving, talk to your doctor. They may be able to adjust the dose or the timing of doses, or change the medicine to one that causes less drowsiness. ✔ Consider other options instead of driving, such as rides with family/whānau and friends, taxi, bus or, train.

How to make sure you are safe to drive

If you are taking medicines and thinking of driving:

know how your medicines can affect you by asking your doctor or pharmacist
check how you feel before and while you drive
stop driving or don’t start driving if you feel impaired.

✔ Ask your doctor or pharmacist if the medicine you are given affects driving and whether it is safe for you to drive.

✔ Read your medicine labels to see if it can affect your driving.

✔ If you feel that the medicine you are taking is affecting your driving, talk to your doctor. They may be able to adjust the dose or the timing of doses, or change the medicine to one that causes less drowsiness.

✔ Consider other options instead of driving, such as rides with family/whānau and friends, taxi, bus or, train.

How can medicines affect driving?

Some medicines can affect your concentration (how you focus or pay attention). They can slow your reaction times and cause sleepiness, blurred vision, dizziness, slowed down movements and fainting, or make you feel anxious or jittery. Do not drive if you have any of these.

Don't stop taking your medicines so you can drive

If you think your medicines are affecting your driving, don't stop taking them or alter the dose without talking to your doctor or pharmacist first.

Don't drive if you have missed a dose of medicine that you need to control symptoms that could affect your driving.

Epilepsy – some people with epilepsy may not be able to drive at all without taking regular medicines. Read more about driving with epilepsy.
Diabetes – drivers with diabetes need to take regular medicines as prescribed because your blood glucose levels may get too high if you miss doses. You should not drive if your blood glucose is too high (hyperglycaemia). High blood glucose levels can make you feel unwell and tired, and may affect your ability to drive. Read more about driving with diabetes.

Which medicines are most likely to affect driving?

Always ask your doctor or pharmacist if your medicines are likely to affect your driving. Some types of medicines known to affect driving include:

sleeping pills, benzodiazepines and zopiclone
some antidepressants
some pain relievers
some medicines for epilepsy
some heart medicines
some medicines for diabetes
some medicines for your eyes
some antihistamines for allergies
cold and flu medicines
diet pills, 'stay awake' drugs and other medicines containing stimulants (eg, caffeine).

Note: Different combinations of medicines and health conditions can affect people differently.

Video – learn if you are safe to drive when taking any medicines.

(NZTA, 2018)

How long should I avoid driving for?

It is important not to drive until you know how your medicine affects you. Some medicines only have short-term effects when you first start taking them or when you change the dose. This means you might only need to stop driving for a few days until your body adjusts.

However, for other medicines you need to stop driving while you are taking them. Learn to know how your body reacts to the medicines and supplements you are taking. Keep track of how you feel and when the effects occur.

Alcohol, medicines and driving

Drinking alcohol and taking medicines that affect driving increases your risk of having a car crash. It can make you 23 times more likely to have a fatal crash (that causes death) than drivers who have taken none of these.

Alcohol can affect your coordination, reaction time, sleepiness and more. Even though you might be under the legal alcohol limit, you might still be affected and unable to drive.

Be prepared and plan ahead

If you are taking medicines that affects your driving, talk to the people you live with about how your medicines may impair your driving so they can share the driving whenever you need them to.

Think about the following scenarios:

Have a plan for emergencies or unplanned trips. How will you get to an after hours clinic or the hospital if you are unable to drive?
Have a plan for any change in routine. If you take sleeping tablets at night, what will you do differently if you need to drive late at night or very early the next morning? Or if you take your medication with dinner, what will you do differently if you’re planning an after dinner trip to friends in the next suburb?
Plan your alternatives to driving. Could you share a ride with neighbours or workmates, work from home, take the bus or get a lift with friends? Could you delay your trip to another time of day or to another day?

Older adults, medicines and driving

Medicines that usually cause drowsiness and changes in concentration effect older people more because of age-related changes in the way your body breaks down medicines. This is of concern because older people often take several medicines to stay well, including some that may affect driving. Combinations of medicines can cause more side effects.