Teen Marijuana Facts and Health Risks


While most teens using marijuana do not go on to use other drugs, long-term studies of high school students show that few young people use other illegal drugs without first trying marijuana. For example, the risk of using cocaine is much greater for those teens who have tried marijuana than for those who have never tried it. Using marijuana puts children and teens in contact with people who are users and sellers of other drugs. So, a teen using marijuana is more likely to be exposed to and urged to try other drugs.


Marijuana is used in many ways. The most common method is smoking loose marijuana rolled into a cigarette called a “joint” or “nail.” Sometimes marijuana is smoked through a water pipe called a “bong.” Others smoke “blunts”—cigars hollowed out and filled with the drug. And some users brew it as tea or mix it with food.


Some people mistakenly believe that “everybody’s doing it” and use that as an excuse to start using marijuana themselves. Well, they need to check the facts, because that’s just not true. According to a 2008 survey, called Monitoring the Future, about 6 percent of 8th-graders, 14 percent of 10th-graders, and 19 percent of 12th-graders had used marijuana in the month before the survey. In fact, marijuana use declined from the late 1990s through 2007, with a decrease in past-year use of more than 20 percent in all three grades combined from 2000 to 2007. Unfortunately, this trend appears to be slowing, and marijuana use remains at unacceptably high levels, as the most commonly used illegal drug.


For some people, smoking marijuana makes them feel good. Within minutes of inhaling, a user begins to feel “high,” or filled with pleasant sensations. THC triggers brain cells to release the chemical dopamine. Dopamine creates good feelings—for a short time. But that’s just one effect… Loss of coordination can be caused by smoking marijuana. And that’s just one of its many negative effects. Marijuana affects memory, judgment, and perception. Under the influence of marijuana, a teen could fail to remember things just learned, have their grade point average drop, or crash a car. Also, since marijuana can affect judgment and decision making, using it can cause a teen to do things they wouldn’t do when they are thinking straight—such as risky sexual behavior, which can result in exposure to sexually transmitted diseases, like HIV, the virus that causes AIDS; or getting in a car with someone who’s been drinking or is high on marijuana. It’s also difficult to know how marijuana will affect a specific person at any given time, because its effects vary based on individual factors: a person’s genetics, whether they’ve used marijuana or any other drugs before, how much marijuana is taken, and its potency. Effects can also be unpredictable when marijuana is used in combination with other drugs.


The Brain when people smoke marijuana for years they can suffer some pretty negative consequences. For example, because marijuana affects brain function, your ability to do complex tasks could be compromised, as well as your pursuit of academic, athletic, or other life goals that require you to be 100 percent focused and alert. In fact, long-term users self-report less life satisfaction, poorer education, and job achievement, and more interpersonal and mental health problems compared to non-users. Marijuana also may affect your mental health. Studies show that early use may increase your risk of developing psychosis [a severe mental disorder in which there is a loss of contact with reality, including false ideas about what is happening (delusions) and seeing or hearing things that aren’t there (hallucinations)], particularly if you carry a genetic vulnerability to the disease. Also, rates of marijuana use are often higher in people with symptoms of depression or anxiety—but it is very difficult to determine which came first, so we don’t yet know whether they are causally related. Lungs and Airways People who abuse marijuana are at risk of injuring their lungs through exposure to respiratory irritants and carcinogens found in marijuana smoke. The smoke from marijuana contains some of the same chemicals found in tobacco smoke; plus, marijuana users tend to inhale more deeply and hold their breath longer, so more smoke enters the lungs. Not surprisingly, marijuana smokers have some of the same breathing problems as tobacco smokers—they are more susceptible to chest colds, coughs, and bronchitis than nonsmokers. And, even though we don’t know yet whether or how marijuana use affects the risk for lung and other cancers—why take the risk?