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Although marijuana is legal for medical use in Oklahoma, the Oklahoma Highway Safety Office (OHSO) recognizes that there is a common misperception about it. Some claim smoking or ingesting marijuana actually makes them a better driver. Others believe that because it is prescribed, it is safe to go about everyday activities like driving while under the influence of it.

The truth about marijuana is that when you feel different, you drive different. Drugged or buzzed driving is still impaired driving.

Marijuana use can result in:

  1. Slower decision-making and reaction time
  2. Impaired peripheral/side vision
  3. Difficulty staying in traffic lanes and judging distances
  4. Reduced coordination and attention span

Safety and Intervention Tips

Prevention is the most effective way to reduce injury, death and other consequences of driving while high. If someone you know attempts to drive while drugged, follow these tips:

Timeline of Marijuana's Effects

If you or someone you know uses marijuana, whether it’s smoking or ingesting, it’s vital to understand the timeline of its effects, which can vary depending on the product type (edibles vs. joints, for example) and the person using it. Studies from the National Highway Traffic Safety Administration (NHTSA) support this timeline of effects:

10-30 Minutes — The approximate time from the last puff until peak effects occur*
+ 2-5 Hours — The approximate length of time a driver is impaired after their last use**
2+ Weeks — The amount of time THC can be detected (in a blood test) after the last use

*Edibles and other methods of marijuana consumption have different timelines. Do not use these products and drive.
**Some people may be impaired for more than five hours after using marijuana (particularly those who have not developed a tolerance to it).

Last Modified on Dec 11, 2023
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