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The Facts About Recreational Marijuana

A rolled up marijuana cigarette as well as dried green leaves loosely spilled out from a canister.

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

Marijuana is the most often used illegal drug in the United States. It comes from the hemp plant (cannabis sativa). The chemicals in marijuana are found in the leaves and flowering shoots. THC is the most well-known. There are also man-made chemicals that act like THC, but they are much stronger than THC. They are "synthetic marijuana" and sold under brand names such as "K2," "Kronic," or "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 or bong, or as a blunt (a cigar casing that has been filled with marijuana). It might also be mixed in food or brewed as a tea. A more concentrated form called hashish is made from the tops of female plants. It has the highest concentration of THC.

Some studies suggest that some types of marijuana are now stronger than in the past.

Marijuana users can develop dependence or addiction through ways similar to other drugs of abuse including alcohol and tobacco.

Symptoms of use

These are some effects of marijuana use:

  • Feeling of joy, relaxation

  • Increased sight, hearing, and taste perceptions

  • Increased appetite

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

  • False sense of time

  • Trouble thinking and problem solving that can also affect driving 

  • Unable to tell the difference between oneself and others

  • Anxiety or panic reactions or being overly suspicious and distrustful

Signs of marijuana use include:

  • Being dizzy

  • Having trouble walking

  • Being silly and giggly for no reason

  • Having red, bloodshot eyes

  • 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 withdrawal or separation from others, depression, excessive tiredness, carelessness with grooming, hostility, and relationships with family members and friends that get worse and worse. In addition, changes in school performance, skipping or missing school, 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 items, 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. For example, the chance 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. Some of these are felt right away and others damage a person's health over time. Marijuana affects short-term memory and the ability to handle difficult tasks. With the use of stronger types of marijuana, even simple tasks can be difficult.

Because of the drug's effects on the ability to understand and on reaction time, users are more often involved in car crashes than people who don't use marijuana. They also may have more risky sexual behavior. There is a strong link between drug use, unsafe sex, and the spread of sexually transmitted diseases.

Under the influence of marijuana, students may find it hard to study and learn because it hurts the ability to concentrate and pay attention. And young athletes may perform poorly. THC affects timing, movements, and coordination.

Synthetic marijuana products have the potential for more serious adverse effects. Hallucinations, kidney damage, seizures, and even death have been reported with the use of these products.

Other problems

Marijuana smoke contains some of the same compounds that cause cancer like 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 like 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. Teens often refer to these stories and laws to defend their use of marijuana. 

No magic bullet can prevent teenage drug use. But parents can influence their children by setting clear rules regarding no drug use. They can talk to their children about the dangers of using marijuana and other drugs, and remain very involved in their children's lives.

Medical Reviewers:

  • Brown, Kim, APRN
  • Perez, Eric, MD