Marijuana is a drug made from the dried leaves of the cannabis plant and is the most widely used illicit drug in the United States. The chemical in marijuana that is responsible for causing the “high” is called THC. In the 1990’s, the average THC content was almost 4%. The current most powerful strain of marijuana has a THC content of 33%! The effects from marijuana begin almost immediately and can last for many hours. However, marijuana’s effects on the mind can last for days.

Some effects of marijuana include:

  • nausea/vomiting
  • breathing issues
  • memory problems/lower IQ

Marijuana withdrawal symptoms include:

  • drug cravings
  •  insomnia
  • decreased appetite


National Institute on Drug Abuse for Teens: Marijuana