Research Reports: Marijuana Abuse
- Letter From the Director
- What is marijuana?
- What is the scope of marijuana use in the United States?
- How does marijuana produce its effects?
- How does marijuana use affect your brain and body?
- Is there a link between marijuana use and mental illness?
- Is marijuana addictive?
- How does marijuana use affect school, work, and social life?
- Does marijuana use affect driving?
- Can marijuana use during pregnancy harm the baby?
- Available treatments for marijuana use disorders
- Where can I get more scientific information on marijuana abuse?
- Glossary
- References
What is marijuana?

Marijuana—often called pot, grass, reefer, weed, herb, Mary Jane, or MJ—is a greenish-gray mixture of the dried, shredded leaves, stems, seeds, and flowers of Cannabis sativa—the hemp plant. Most users smoke marijuana in hand-rolled cigarettes called joints, among other names; some use pipes or water pipes called bongs. Marijuana cigars, or blunts, are also popular. To make blunts, users slice open cigars, remove some of the tobacco, and mix the remainder with marijuana (Timberlake 2009). Marijuana also is used to brew tea and sometimes is mixed into foods.
This page was last updated September 2010.
Research Reports
This series of reports simplifies the science of research findings for the educated lay public, legislators, educational groups, and practitioners. The series reports on research findings of national interest.
Featured Publication
Drugs, Brains, and Behavior - The Science of Addiction
As a result of scientific research, we know that addiction is a disease that affects both brain and behavior.
External link, please review our disclaimer.
External link, please review our disclaimer.
External link, please review our disclaimer.





