The new THC limit of 3.5 ng/ml in road traffic, MPU orders and fitness-to-drive assessment: what cannabis-consuming drivers in Germany need to know now.
## New THC Limit Since October 2024
Germany introduced a science-based THC road traffic limit of 3.5 ng/ml blood serum in October 2024. Below this limit, no administrative offence exists (unless impairment is evident or there is mixed consumption with alcohol ≥0.2 ‰).
## When Is an MPU (Medical-Psychological Assessment) Ordered?
The MPU ("Idiotentest") can be ordered by licence authorities when: - A driver is caught with >3.5 ng/ml THC - Regular cannabis use is established (even without road traffic offences) - Mixed consumption (cannabis + alcohol) is involved
## The MPU Assessment Process
The MPU consists of: (1) medical examination including abstinence proof via lab work (6–12 months abstinence often required); (2) cognitive performance tests; (3) psychological interview assessing separation ability (Trennungsvermögen) – the ability to always separate consumption from driving.
## Key Rule
The safest approach: if you have consumed cannabis, do not drive. THC can impair driving ability for hours after consumption, even when the subjective feeling of intoxication has passed.
About this article
Written and reviewed by the BlattWerk e.V. editorial team — licensed cultivation association in Hildesheim. Our articles are based on current legislation, scientific publications and our practical experience as a Cannabis Social Club.
Last updated: 2026-06-17 · Found an error or something missing? Let us know
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