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The Facts About Marijuana

Knowing about marijuana can help you recognize its use in children and others and help a user seek treatment.

Marijuana is the most frequently used illegal drug in the United States, according to the National Institute on Drug Abuse (NIDA). It comes from the hemp plant (cannabis sativa). The chemicals in marijuana that causes its effects are cannabinoids, which are found in the leaves and flowering shoots. Of the cannabinoids, THC (delta-9-tetrahydrocannabinol) is the most well known. There are also man-made chemicals that resemble THC (synthetic cannabinoids) but are much stronger than THC. They are sometimes called "spice."

Marijuana can be used in several forms. As a dry, shredded green/brown mix of flowers, stems, seeds, and leaves, it is usually smoked as a cigarette (joint), in a pipe (bong) or as a blunt, a cigar casing that has been filled with marijuana. It can be used by vaporizing or "vaping" in devices similar to electronic cigarettes. It might also be mixed in food or brewed as a tea. A more concentrated, resinous form called hashish is made from the tops of female plants and has the highest concentration of THC.

Stronger forms of marijuana are available today than in the 1970s, and its potency continues to increase even now.

Marijuana users can develop addiction (marijuana dependence) through mechanisms similar to other drugs of abuse including alcohol, tobacco, and opiates. 

Symptoms of use

According to the NIDA, nearly 17 million Americans aged 12 or older used marijuana at least once in the month prior to being surveyed. 

These are some effects of marijuana use:

  • Euphoria (feeling of joy), relaxation

  • Increased visual, auditory and taste perceptions

  • Increased appetite, called "the munchies"

  • Loss of coordination, making it difficult, even dangerous, to perform tasks such as driving a car

  • Distorted sense of time

  • Difficulty thinking and problem solving that can also affect driving skills 

  • Depersonalization (inability to distinguish oneself from others)

  • Anxiety or panic reactions or severe paranoia

Signs of marijuana use include being dizzy and having trouble walking; being silly and giggly for no reason; having red, bloodshot eyes; and having a hard time remembering things that just happened.

When the early effects fade after a few hours, the user can become very sleepy.

What to look for

Parents should look for isolation or withdrawal, depression, fatigue, carelessness with grooming, hostility and deteriorating relationships with family members and friends. In addition, changes in academic performance, increased absenteeism or truancy, lost interest in sports or other favorite activities and changes in eating or sleeping habits could be related to drug use.

Parents should be aware of signs of drugs and drug paraphernalia, including pipes and rolling papers; odor on clothes and in the bedroom; use of incense and other deodorizers; and the use of eye drops.

Long-term studies of high school students show few young people use other drugs without first trying marijuana. The chances that a child will try using cocaine is much higher for those who have tried marijuana than for those who have never tried it.

Harmful effects

Marijuana can be harmful in several ways, both through immediate effects and damage to health over time. It hinders the user's short-term memory, and the person may have trouble handling complex tasks. With the use of more potent varieties of marijuana, even simple tasks can be difficult.

Because of the drug's effects on perceptions and reaction time, users are more often involved in auto crashes than nonusers. They also may become involved in risky sexual behavior. A strong link exists between drug use, unsafe sex and the spread of sexually transmitted diseases including HIV, the AIDS-causing virus.

Under the influence of marijuana, students may find it hard to study and learn because it diminishes the ability to concentrate and pay attention, and young athletes may perform poorly; timing, movements and coordination all are affected by THC.

Other problems

Marijuana smoke contains some of the same cancer-causing compounds as tobacco, sometimes in higher concentrations.

Treatments for marijuana dependence are similar to therapies for other drug-abuse problems. These include detoxification, behavioral therapies and regular attendance at support-group meetings, such as those sponsored by Narcotics Anonymous.

Recent news stories and states' laws regarding possible medical benefits of marijuana and casual or recreational use of marijuana do not apply to children and teenagers. This is a common point of argument or distraction brought up by teens to justify their use of marijuana. 

No magic bullet can prevent teenage drug use. But parents can be influential by setting clear rules regarding no drug use, talking to their children about the dangers of using marijuana and other drugs, and remaining actively engaged in their children's lives.