marijuana: Quick Facts

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Last updated

Nov. 3, 2026

News •

Cannabis use linked to an increased risk of cardiovascular disease, especially strokes • Nov. 2, 2026, 5:00 AM ET (Medical Xpress)

Facts

Also Known As	weed • marihuana • reefer • grass • tea • pot

Photos and Videos

Map of the United States displaying the legal status of marijuana by state as of late 2024. States where marijuana is legal for adult use are shaded green, states where it is illegal are shaded orange, and states with conditionally decriminalized possession are marked with a lighter orange. Additional symbols indicate where marijuana is legal for medicinal use or where only low-THC medicinal use is permitted.

marijuana plants

Marijuana (Cannabis sativa) with (left) male plant, (right) female plant

The chemistry of marijuana

saliva test for cannabis

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Topics

The Dope on Dope: 8 Facts About Marijuana Why Is Marijuana Illegal in the U.S.?What Is the Difference Between Hemp and Marijuana?What Are the Biological Effects of Marijuana Use?Medical marijuana drug use Recreational marijuana 9 Mind-Altering Plants medical cannabis The CDC warns of “mass THC intoxication events via food”hashish

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drug use: Cannabis

Key People

Adams, Roger

Roger Adams

American chemist