Marijuana is a green, brown, or gray mixture of dried, shredded leaves, stems, seeds, and flowers of the hemp plant. You may hear marijuana called by street names such as pot, herb, weed, grass, boom, Mary Jane, gangster, or chronic. There are more than 200 slang terms for marijuana.
Sinsemilla (sin-seh-me-yah; it's a Spanish word), hashish (hash for short), and hash oil are stronger forms of marijuana.
All forms of marijuana are mind-altering. In other words, they change how the brain works. They all contain THC (delta-9-tetrahydrocannabinol), the main active chemical in marijuana. They also contain more than 400 other chemicals. Marijuanas effects on the user depend on its strength or potency, which is related to the amount of THC it contains. The THC content of marijuana has been increasing since the 1970s.
Marijuana is usually smoked as a cigarette (called a joint or a nail) or in a pipe or a bong. Recently, it has appeared in cigars called blunts. THC in marijuana is strongly absorbed by fatty tissues in various organs. Generally, traces (metabolites) of THC can be detected by standard urine testing methods several days after a smoking session. However, in chronic heavy users, traces can sometimes be detected for weeks after they have stopped using marijuana.
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