For a broader overview of cannabis-related driving impairment, see the cannabis driving guide.
California rule: do not drive impaired
California's DUI rules apply to alcohol and drugs. The California DMV says it is illegal to drive while under the influence of any drug that affects safe driving. Cannabis can impair judgment, reaction and coordination; a legal purchase does not change the driving rule.
If cannabis may affect you, do not drive. Arrange a sober driver, taxi, rideshare, public transit or a place to stay. Do not rely on feeling "mostly normal" as a safety test.
Cannabis inside a vehicle
California DMV says smoking or eating cannabis is illegal while driving or riding as a passenger in a vehicle. The handbook notes that the rule does not apply to a passenger in a bus, taxi, camper or motorhome. If cannabis is in a vehicle, an open container must be kept in the trunk or an area where passengers do not sit; the same handbook exception applies. Check the handbook for scope and current detail.
Keep products in their original closed packaging where possible, and store them where children and pets cannot reach them. Do not use a private vehicle as a place to consume cannabis.
Why a fixed wait time is not reliable
There is no single waiting period that proves someone is safe to drive after cannabis. Health Canada says effects vary with how much and how often a person used cannabis and whether it was smoked or ingested. Some effects, including drowsiness, can last up to 24 hours.
This page does not estimate an individual's impairment, tell anyone when they can drive, or describe a way to pass a roadside test. If there is doubt, do not drive.
A safer trip checklist
- Decide on a sober ride before using cannabis.
- Do not use cannabis in a private car.
- If transporting a product, follow California DMV's container guidance and keep it secured.
- Do not mix cannabis with alcohol before driving; combined use increases impairment risk.
- For urgent travel, ask someone sober to drive or choose another transport option.
Quick FAQ
Is it legal to drive after using cannabis in California?
California DMV says it is illegal to drive while under the influence of any drug that affects safe driving. Do not drive if cannabis may impair you.
Can I use cannabis while riding as a passenger?
California DMV says smoking or eating cannabis in a vehicle is illegal while driving or riding as a passenger, with stated exceptions for passengers in a bus, taxi, camper or motorhome. Check the handbook for scope.
How long should I wait before driving?
No single waiting period guarantees safe driving. Health Canada says effects vary by amount, frequency and route, and some effects such as drowsiness may last up to 24 hours. Arrange another ride.
How should I store cannabis in my car?
California DMV says an open container must be kept in the trunk or an area where passengers do not sit. Check the current DMV guidance for exceptions and detail.
Sources
- California DMV: Alcohol and Drugs -- California Driver Handbook; checked 2026-09-25.
- Health Canada: Cannabis impairment -- opened 2026-09-25; page details 2026-04-01.
Sources checked 2026-09-25.