Fitness to drive (Fahrfähigkeit)

Fitness to drive (Fahrfähigkeit) is the physical and mental capacity required to drive a vehicle at a given time. Anyone who lacks it because of alcohol, narcotics, medicines or other reasons is unfit to drive for that period and must not drive a vehicle (Art. 31 para. 2 SVG). This applies to everyone, with or without a prescription.

Zero tolerance and the exception

For THC, Swiss road traffic law applies zero tolerance: unfitness to drive is deemed proven if THC is detected in the driver's blood (Art. 2 para. 2 let. a VRV). The same applies to the other substances listed in that paragraph (Art. 2 para. 2 VRV). THC counts as detected from 1.5 micrograms per litre of blood (Art. 34 let. a VSKV-ASTRA).

For persons who can prove that they take one of the listed substances according to a medical prescription, detection of the substance alone does not prove unfitness (Art. 2 para. 2ter VRV). The general rule still applies: anyone who is actually unfit must not drive (Art. 31 para. 2 SVG).

Consequences of driving while unfit

• Driving a motor vehicle while unfit for reasons other than a qualified alcohol level, for example under the influence of narcotics, is punishable by a custodial sentence of up to three years or a monetary penalty (Art. 91 para. 2 let. b SVG).
• Riding a non-motorised vehicle such as a bicycle while unfit is punishable by a fine (Art. 91 para. 1 let. c SVG).
• Driving a motor vehicle while unfit because of narcotics or medicines is a serious offence. The learner's or driving licence is then withdrawn for at least three months, and for longer after earlier withdrawals (Art. 16c SVG). The cantonal road traffic office orders this measure in addition to any criminal penalty.

Our article on driving with a prescription and the question on the road traffic office explain the practical side.