The Short Answer

You may be able to drive the day after smoking cannabis. But there is no safe cutoff time. The answer depends on your body, the amount you smoked, and how often you use cannabis.

can you drive the day after smoking cannabis

For occasional users, impairment from a single smoked dose lasts 1 to 4 hours. Peak impairment is 1.5 to 3 hours after smoking. By the next day, 8 to 12 hours later, most occasional users show no driving impairment. But some studies find residual effects up to 24 hours.

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For users who use cannabis every day, THC builds up in the body. Impairment can last longer. A 2020 study found heavy users had driving impairment 12 hours after smoking. Another study found users who use every day had impairment for up to 24 hours.

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How Long THC Stays in the Body

THC detection times vary. Blood: 1 to 2 days after occasional use. Up to 5 days or more for heavy users. Urine: 3 to 30 days. Hair: up to 90 days. Detection does not equal impairment. You can have THC in your blood and still drive without impairment. You can also be impaired with low THC levels.

Cannabis and Driving Laws for CBD Users

Legal Limits by State

Many states have per se THC limits. Colorado and Washington have a 5 ng/mL THC blood limit. Arizona has zero tolerance. In these states, you can be charged with DUI even if you are not impaired. Penalties include fines, license suspension, and jail.

What to Do

Do not drive if you feel any effects. Wait at least 8 hours after smoking. If you use cannabis every day, wait 24 hours. Do not mix cannabis with alcohol. Do not rely on coffee or cold showers. They do not reduce impairment.

  1. Wait at least 8 hours after smoking.
  2. Do not drive if you feel high.
  3. Use a designated driver.
  4. Check your state law.