Cannabis and Driving in Luxembourg: The 1 ng/mL Rule
Short answer: Do not drive under the influence of cannabis. Luxembourg Police says driving under the influence of drugs is prohibited. The Health Portal quotes the amended road-traffic law as applying when a driver's serum THC level is equal to or greater than 1 ng/mL. It also notes that the provision covers a pedestrian involved in an accident. Luxembourg Health Portal: Cannabis FAQ · Luxembourg Police: Drugs
What the threshold does--and does not--tell you
The 1 ng/mL figure is the legal threshold described by official Luxembourg sources. The Health Portal says that, in practice, the threshold means zero tolerance for driving under the influence of cannabis. Do not treat the number as a personal impairment test, a safe-to-drive target, or a guarantee about a roadside or laboratory result.
The Health Portal says cannabis--especially products with high THC--can cause dizziness or drowsiness and impair judgment and tasks requiring skill. Those effects are a separate safety reason not to drive after use; feeling alert is not proof that the legal threshold is met.
Is there a safe number of hours to wait?
The official pages checked for this draft state the threshold and describe possible effects, but do not give a universal waiting period after use. They do not support a promise such as "wait X hours and you are safe/legal." Avoid driving rather than relying on a timer, dose estimate, product type, or how you feel.
Practical answers
- I feel normal. Can I drive? These sources provide no self-check that clears a driver. The law uses a serum threshold, and the Health Portal warns that judgment and skilled performance can be affected. Do not drive if you may be under the influence.
- Does home use make driving exempt? No. Police says permitted cannabis consumption in certain circumstances does not change the prohibition on driving under the influence.
- Does the threshold measure impairment? The source states a legal concentration threshold. It does not describe it as an individualized measure of functional impairment or as a safe-driving calculator.
- What about prescribed cannabis? This draft does not decide individual medical or licensing questions. The Health Portal has separate patient guidance; ask the prescriber and relevant authority, and do not drive if treatment may affect you.
Related: Luxembourg home-use and cultivation guide.
This is a summary of official public guidance, not legal or medical advice. The Police drugs page says it was last updated 3 February 2025; the Health Portal FAQ says it was last updated 1 December 2025. Recheck both live sources before acting.