Firstly, it is important to remember that many medications, whether they be prescribed by a doctor or those bought 'over-the-counter' (OTC) from a supermarket or a pharmacy, can affect your ability to drive safely. Research has found that the use of some of these pharmaceutical products have led to a significant number of road deaths.
The initial test used in roadside drug testing (RDT) (or mobile drug testing (MDT) as it is called in NSW) is a simple saliva test. This test is used to identify three illicit drugs - cannabis (or to be more specific, the active component of cannabis which is called THC), ecstasy (MDMA) and methamphetamine (speed or ice). It will not detect the presence of prescription drugs, including those medicines containing amphetamine-like substances, such as cold and flu tablets. You cannot test positive for amphetamine as you are only being tested for methamphetamine - amphetamine and methamphetamine are not the same drug. Taking ADHD medication such as dexamphetamine alone will also not produce a positive result on the initial roadside drug test. Once again, dexamphetamine and methamphetamine are not the same so it won't be identified in this initial test.
Some antidepressants may also impair driving ability, particularly those that have a sedative effect and young people should be encouraged to speak to their doctor about the effect of their prescribed medication on driving, particularly if they have been using the drug for some time. Their doctors should be made aware that they are now driving and, if the medication does have a negative effect on driving skills, an alternative product may need to be prescribed. If you have only recently started to drive it may be a good idea to take your medication as you usually do and then ask a parent or a responsible friend to take a drive with you shortly afterwards and tell you whether they believe your driving is impaired in any way.
If a driver is stopped for RDT or other reasons at the roadside, however, and their behaviour or driving is erratic and police suspect they are under the influence of any drug – legal, illegal or pharmaceutical, the police can require them to undergo blood and urine testing. The tests cover a large range of legal and illegal substances that can impair drivers and can lead to a charge of driving under the influence (DUI), which has serious penalties. If the drug is adversely affecting the driver's driving ability, then regardless of whether it is prescribed or bought 'over the counter' then they can be charged with drug driving.
If you are on any medication, make sure you talk to your doctor about what impact the drug may have on your driving ability. At the very least, read the instructions and warning labels. Even over-the-counter medications such as cold and flu preparations can impair driving ability, particularly if they are not taken as directed. Antihistamines, which many young people use to treat allergies such as hayfever, can often cause drowsiness and even though 'non drowsy' preparations can be purchased, it is still extremely important that you read the packaging carefully before using and then driving. If you are in any doubt, ask the pharmacist about the drug’s potential effect on driving.
If there is any chance that the medication being taken could affect your driving ability, the message is clear - do not drive.
First published: April 2019