Medical-marijuana legalization doesn't seem to lead to an increase in pot usage for teenagers.
For both teens and adults, alcohol appears more dangerous for the brain than marijuana is.
Thousands of pot supporters mark the "high" holiday by lighting up at 4:20 p.m. But the celebration may increase the risk of fatal car crashes.
It's really tricky to measure how much marijuana a person has used on a given day — and how impaired their driving may be as the result of that use — a new review says.
Marijuana is the most commonly used illicit drug in pregnant woman, and now its use is increasing, a new study finds.
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