Marijuana is a green or gray mixture of dried, shredded flowers and leaves of the hemp plant Cannabis sativa.

Before the 1960s, many Americans had never heard of marijuana, but today it is a widely used illegal drug. It is usually smoked as a cigarette (called a "joint" or a "nail") or in a pipe or bong. In recent years, marijuana has appeared in blunts (cigars that have been emptied of tobacco and refilled with marijuana). Marijuana cigarettes or blunts have come to sometimes include crack cocaine, a combination known by various street names, such as "primos" or "woolies." Joints and blunts are also sometimes dipped in PCP and are called "happy sticks," "wicky sticks," "love boat" or "tical." Some users mix marijuana into foods or use it to brew tea.

Slang terms for drugs change quickly, and they vary from one part of the country to another. They may even differ across sections of a large city. Terms from years ago, such as pot, herb, grass, weed, Mary Jane and reefer are still used. You might also hear the names Aunt Mary, skunk, boom, gangster, kif, or ganja. There are also street names for different strains or "brands" of marijuana, such as Bubble Gum, Northern Lights, Fruity Juice, Afghani No.1, and a number of Skunk varieties. One book of American slang lists more than 200 terms for various kinds of marijuana.

Cannabis is a term that refers to marijuana and other drugs made from the same plant. Strong forms of cannabis include sinsemilla (sin-seh-me-yah), hashish (hash for short) and hash oil.

All forms of cannabis are mind-altering (psychoactive) drugs; they all contain delta-9-tetrahydrocannabinol (THC), the main active chemical in marijuana. They also contain more than 400 other chemicals.

Marijuana's effect on the user depends on the strength or potency of the THC it contains. The strength of the drug is measured by the average amount of THC in test samples of marijuana confiscated by law enforcement agencies. They found:

  • Most ordinary marijuana contained, on average, 7 percent THC.
  • Sinsemilla, made from the buds and flowering tops of female plants, contained 12 percent THC on average, ranging from less than 1 percent to 27 percent.
  • Hashish (the sticky resin from female plant flowers) had an average of 10 percent THC, ranging from 1 percent to 26 percent.

The "Monitoring the Future Survey," conducted yearly, includes students from the 8th, 10th, and 12th grades. The recent survey found that 15.7 percent of that year's 8th-graders had tried marijuana at least once, and that among 10th-graders, 14.2 percent were "current" users (that is, had used within the past month). Among 12th-graders, 42.3 percent had tried marijuana at least once, and about 18 percent were current users.

Cannabis/Marijuana. Last reviewed 12/31/1969
  • New England Journal of Medicine
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  • Archives of General Psychiatry
  • International Journal of Clinical Pharmacology and Therapeutics
  • National Institute on Drug Abuse, Child Abuse and Neglect (NIDA)
  • Journal of Clinical Pharmacology
  • Science
  • Behavioral Pharmacology
  • National Institute on Drug Abuse
  • Western Journal of Medicine
  • Journal of the American Medical Association
  • University of Michigan, News and Information Services
  • National Institutes of Health -U.S. National Library of Medicine