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Ask a Stoner: Waiting to Drive After Smoking Pot

There isn’t much science to sit on, but stay safe instead of sorry.
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Dear Stoner: How many hours after smoking marijuana does it take for you to be able to drive?
Dewayne

Dear Dewayne: This isn’t an answer we can just pull out of our butt cracks for you. There isn’t enough science to sit on in order to give you an exact time frame, but our asses aren’t completely bare, either. Because cannabis impairment isn’t as easy to determine through breath and blood levels, law enforcement still doesn’t have an exact way of determining how high you really are, though advancements are being made in breath and blood testing to detect THC levels and determine when a driver last consumed.
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A Colorado county sheriff measures a driver's impairment levels during a 2018 driving experiment that measures the skills of alcohol and cannabis users.
Thomas Mitchell
Most state laws surrounding cannabis DUIs focus on the amount of THC in the blood, measuring it in nanograms (Colorado’s limit is 5 nanograms). However, daily users are likely to have high levels of THC even if they last smoked the day before, while novice and new users will have low levels of THC in their blood several hours after consumption, despite still being baked.

It all comes down to your tolerance and the potency of the cannabis. Still, we’d recommend waiting at least a couple hours after you toke before you think about driving, no matter what.

Send questions to [email protected].