Marijuana is a dry, shredded green and brown mix of leaves, flowers, stems, and seeds from the hemp plant Cannabis sativa. In a more concentrated, resinous form, it is called hashish, and as a sticky black liquid, hash oil. The main psychoactive (mind-altering) chemical in marijuana is delta-9-tetrahydrocannabinol, or THC. Learn more
To learn more about our marijuana research, see Marijuana Research at NIDA.
Statistics and Trends
|Drug||Time Period||Ages 12 or Older||Ages 12 to 17||Ages 18 to 25||Ages 26 or Older|
- Marijuana: Facts for Teens
- Marijuana: Download the Facts Poster (Teaching Guide)
- Heads Up: Real News About Drugs and Your Body- Year 11-12 Compilation for Students
- Heads Up: Real News About Drugs and Your Body- Year 11-12 Compilation for Teachers
- Marijuana’s Lasting Effects on the Brain, (Message from the NIDA Director, September 2012)
- NIDA for Teens: Marijuana
Get more information on Emerging Trends, we will update this page with the latest research findings as they develop.
Other Articles of Interest
Explores the latest research on marijuana, including the scope of marijuana use in the U.S., health consequences, its effects on every-day activities, available treatments.
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