Drugs and medicines
⏱️ 4 min read
Driving demands quick reactions and full mental clarity. Yet drugs and certain medicines reduce attention, lengthen reaction time and distort judgement. In Belgium the law is clear: for illegal drugs it is zero tolerance; for medicines, the driver remains responsible for their fitness to drive. Here is what you need to know to drive safely and pass the exam.
✨ Key takeaways
- For illegal drugs it is zero tolerance: no tolerated threshold.
- Screening is done by saliva test, confirmed by a blood sample.
- Refusing the test is punished as a positive result.
- High-risk medicines carry a yellow, orange or red triangular pictogram.
- Always read the leaflet and ask your doctor or pharmacist for advice.
- The driver alone is responsible for their fitness to drive.
Why drugs and medicines are dangerous at the wheel
Good driving rests on three abilities: perceiving what is happening around you, deciding correctly and acting at the right moment. Drugs, like certain medicines, disrupt all three stages. They can cause drowsiness, blurred vision, deceptive euphoria, overestimation of your abilities or, on the contrary, slowed movements. The danger is all the greater because the driver is often unaware that their performance has dropped.
Illegal drugs: zero tolerance
Unlike alcohol, there is no tolerated threshold for drugs at the wheel. As soon as a prohibited substance is detected in the body, the offence is established, even if the driver feels perfectly capable of driving. This covers in particular cannabis (THC), cocaine, amphetamines and MDMA, as well as opiates (heroin, morphine).
Screening in three stages
During a check, the police generally proceed in stages:
- A standardised checklist: the officer observes outward signs (eyes, behaviour, speech) to detect probable use.
- The saliva test: a saliva sample allows the presence of drugs to be detected quickly.
- The blood analysis: if the test is positive, a blood sample confirms the offence and measures the exact concentration.
Heavy penalties
Driving under the influence of drugs leads to an immediate driving ban (in practice for several hours), a substantial fine and a risk of disqualification from driving. In the event of reoffending or an accident, the penalties become much harsher. The combination of drugs + alcohol is punished particularly severely.
Medicines: read before you drive
Many commonly used medicines act on the nervous system: sleeping pills, tranquillisers, antidepressants, strong painkillers, certain antihistamines or cough syrups. They can cause drowsiness, reduced alertness, dizziness or vision problems. Taking a medicine is not forbidden, but driving while it reduces your fitness is.
The triangular pictogram on the box
In Belgium, medicines that affect driving carry a triangular pictogram on the box. Its colour indicates the level of risk. You must look out for it and read the leaflet before getting behind the wheel; if in doubt, ask your doctor or pharmacist for advice.
| Colour | Level of risk | What to do |
|---|---|---|
| Yellow (level 1) | Mild or possible effect | Be careful, read the leaflet before driving |
| Orange (level 2) | Potentially significant effect | Do not drive without advice from your doctor or pharmacist |
| Red (level 3) | Major effect | Do not drive; wait until the treatment ends or you get medical clearance |
A few common-sense rules
- Never combine medicines with alcohol: their effects reinforce each other dangerously.
- Respect the doses and the stated times; a sleeping pill taken at night can still be acting in the morning.
- At the start of a treatment, be especially careful: your body needs to adjust.
- At the slightest sign of drowsiness or dizziness, do not get behind the wheel.
❓ Frequently asked questions
Is there a tolerated threshold for cannabis at the wheel?
No. For illegal drugs, including cannabis, Belgium applies zero tolerance. As soon as a trace is detected, the offence is established, regardless of whether you feel fit to drive.
What happens if I refuse the saliva test?
Refusing screening without a valid reason is an offence punished in the same way as a positive test. Refusing is therefore never an advantageous option.
Can I drive after taking a prescribed medicine?
It depends on the medicine. Check the triangular pictogram on the box and read the leaflet. If there is an orange or red pictogram, ask your doctor or pharmacist for advice before getting behind the wheel.
What does the triangular pictogram on my medicine box mean?
It indicates that the medicine can affect driving. Yellow signals a mild effect (caution), orange a potentially significant effect (professional advice required) and red a major effect (do not drive).