By CBSLA Staff

LOS ANGELES (CBSLA) — It may be 4/20, the day that marijuana users have made their own unofficial holiday, but authorities want to remind everyone celebrating the day to consider not getting behind the wheel.

The Automobile Club and the LAPD took the opportunity Monday to remind drivers that operating a vehicle while high is illegal and dangerous. Smoking or ingesting marijuana slows reaction time and clouds judgment.

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And while a breathalyzer doesn’t detect marijuana, if a driver fails a field sobriety test, officers have other ways to determine if a driver is high.

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“We check their blood pressure with the devices here, we’re gonna check their pupil size,” LAPD Officer Jayson Siller said. “Using our penlight, which is going to allow us to test their pupil size under room light conditions, near total darkness and direct light.”

Police officers can also take a blood sample to test it for DUI, he said.

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The Automobile Club says people using marijuana should wait eight hours after smoking, and 10 hours after ingesting edibles, before they get behind the wheel.