Marijuana consists of a mixture of plant products, such as leaves and stems. Hashish is more potent and is comprised of dried cannabis resin and compressed flowers. Marijuana, hashish, and hashish oil are obtained from the plant Cannabis sativa, which grows in tropical and temperate climates. The plasma half-life of THC decreases with increasing use. Smoking cannabis is the most common route of administration.
Absorption is more efficient via smoking than ingestion.
The effects of smoking marijuana begin almost immediately, usually in 2 to 3 minutes. At lower doses the peak effect is seen at 10 to 20 minutes and the duration of effect is 90 minutes to 2 hours. The oral dose of marijuana must be three to five times greater than the smoked dose to produce equivalent effects. Tolerance develops to the desired psychoactive effects of marijuana with prolonged use. Tolerance towards the sedative effects seems to develop before tolerance to the stimulatory effects.