How long should I wait to drive after getting high?

Waiting to drive and understanding THC dosage can help you avoid a DUI.

cannabis in an open container, displayed across a wooden table. A white banner reads “Drugged Driving: Knowing your tolerance”

CDPHE recommendations for safe consumption of cannabis

Colorado experienced an incredibly deadly year on its roadways in 2022, especially for impaired driving. Over 280 lives were lost in impaired driving related crashes, the highest number since 2002. With a new year underway, making decisions that put safety first – for yourself and others – is essential.
One of the best safety measures you can take when consuming cannabis is to wait before you get behind the wheel. The question is: how long do you need to wait before driving? Below is some information from our friends at the Colorado Department of Public Health and Environment (CDPHE).

If you plan to consume cannabis, consider the following guidelines:

  • Wait at least six hours after smoking marijuana containing less than 35 milligrams (mg) THC before driving, biking or performing other safety-sensitive activities.
  • If you’ve smoked more than 35 mg, you need to wait longer.
  • Wait at least eight hours after eating or drinking marijuana containing less than 18 mg THC before driving, biking or performing other safety-sensitive activities.
  • If you’ve consumed more than 18 mg, wait longer. If you have consumed alcohol as well, it’s crucial to wait even longer. Using cannabis and alcohol together enhances the effects of each, causing increased side effects. And some products sold on the illegal market can even cause intoxicating effects that last longer than 12 hours.

In Colorado, the typical marijuana cigarette or joint contains approximately 0.5 grams of marijuana, which means consuming about 60-115 mg of THC. The standard serving size for a marijuana edible is 5-10 mg. However, consuming similar amounts of THC in edibles will typically have stronger effects than if smoked.

Driving impaired should never be an option — your safety and that of those around you matters. Visit the Drugged Driving homepage to learn more about our campaign efforts.