Cannabis, or marijuana, is a psychoactive herb that comes from the cannabis plant. This mind-altering substance is an illegal drug in most states; however, laws are changing, especially in the western regions. Marijuana is a mixture of dried, shredded flowers, as well as leaves of the plant Cannabis sativa. Stronger forms of cannabis include sinsemilla, hashish or hash, and hash oil.
Marijuana is usually smoked, and can be found in electronic cigarettes as well as in cigars that have been emptied of tobacco and refilled with marijuana, known as blunts. Marijuana cigarettes or blunts sometimes include crack cocaine, and some users mix marijuana in food or brew it in tea.
All forms of cannabis are mind-altering, psychoactive drugs, and all forms contain delta-9-tetrahydrocannabinol (THC), the main active chemical in marijuana. Marijuana's effect on the user depends on the amount of THC in which the person is exposed. The potency of the drug is measured by the average amount of THC in test samples confiscated by law enforcement agencies. These samples showed the following:
- Most ordinary marijuana contained, on average, 7 percent THC.
- Sinsemilla, from buds, contained 12 percent THC on average, but ranged from less than 1 percent to 27 percent.
- Hashish, the sticky resin from female flowers, had an average of 10 percent THC, but ranged from 1 percent to 26 percent.
In addition, research that appeared in The Lancet Psychiatry has found that in people who smoke cannabis regularly, or those who smoke it with a high THC potency, are at more at risk for first psychotic episodes.
The Monitoring the Future Survey, conducted yearly, includes students from middle through high school. An important finding from a recent survey is the dramatic increase in vaping by adolescents. There has been a significant increase in the vaping of all three substances nicotine, marijuana, as well as flavoring alone. There has also been little change in marijuana use in this age bracket. Marijuana prevalence rose by .5 percent points to 23.9 percent in 2018, while there was a significant increase in the prior year. Annual prevalence stands at 11 percent, 28 percent, and 36 percent in grades 8, 10, and 12 respectively.