There isn't a single amount of time after using cannabis when it's guaranteed to be safe to drive. The effects vary widely based on the product, dose, how you consumed it, your experience with cannabis, and your own body.
Here are some general guidelines:
- If you smoked or vaped cannabis: Impairment is often strongest during the first 1–3 hours, but it can last 4–6 hours or longer, especially after higher doses.
- If you consumed an edible or drink: Effects take longer to start but last much longer. Impairment can persist 8–12 hours, and sometimes longer with high doses.
- If you still feel any effects—such as being "high," sleepy, slowed down, anxious, having trouble concentrating, or noticing altered perception—you should not drive.
Even if you feel okay, some aspects of driving performance (such as reaction time, attention, and coordination) may still be impaired.
A cautious approach is:
- Wait at least 6 hours after smoking or vaping a low dose before considering driving, and longer if you used a larger amount or still notice any effects.
- Wait at least 8–12 hours after an edible, and longer if it was a high dose or you're still feeling any effects.
If you also consumed alcohol, sedating medications, or other drugs, the risk of impairment increases substantially, and you should not drive until all impairing effects have completely worn off.
If you tell me:
- whether you smoked, vaped, or ate it,
- how much you used (if you know), and
- how long ago you consumed it,
I can give more tailored guidance.
