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What Is Marijuana? Aren't There Different Kinds?

Marijuana is a green, brown, or gray mixture of dried, shredded leaves, stems, seeds, and flowers of the hemp plant. You may hear marijuana called by street names such as pot, herb, weed, grass, boom, Mary Jane, gangster, or chronic. There are more than 200 slang terms for marijuana.

Sinsemilla (sin-seh-me-yah; it's a Spanish word), hashish ("hash" for short), and hash oil are stronger forms of marijuana.

All forms of marijuana are mind-altering. In other words, they change how the brain works. They all contain THC (delta-9-tetrahydrocannabinol), the main active chemical in marijuana. They also contain more than 400 other chemicals. Marijuana's effects on the user depend on the strength or potency of the THC it contains. THC potency of marijuana has increased since the 1970s but has been about the same since the mid-1980s.

How Is Marijuana Used?

Marijuana is usually smoked as a cigarette (called a joint or a nail) or in a pipe or a bong. Recently, it has appeared in cigars called blunts.

How Long Does Marijuana Stay in the User's Body?

THC in marijuana is strongly absorbed by fatty tissues in various organs. Generally, traces (metabolites) of THC can be detected by standard urine testing methods several days after a smoking session. However, in heavy chronic users, traces can sometimes be detected for weeks after they have stopped using marijuana.

How Many Teens Smoke Marijuana?

Contrary to popular belief most teenagers have not used marijuana and never will. Among students surveyed in a yearly national survey, only about one in five 10th graders report they are current marijuana users (that is, used marijuana within the past month). Fewer than one in four high school seniors is a current marijuana user.

Why do Young People Use Marijuana?

There are many reasons why some children and young teens start smoking marijuana. Most young people smoke marijuana because their friends or brothers and sisters use marijuana and pressure them to try it. Some young people use it because they see older people in the family using it.

Others may think it's cool to use marijuana because they hear songs about it and see it on TV and in movies. Some teens may feel they need marijuana and other drugs to help them escape from problems at home, at school, or with friends.

No matter how many shirts and caps you see printed with the marijuana leaf, or how many groups sing about it, remember this: You don't have to use marijuana just because you think everybody else is doing it. Most teens do not use marijuana!

What Happens If You Smoke Marijuana?

The way the drug affects each person depends on many factors, including:

• user's previous experience with the drug
• how strong the marijuana is (how much THC it has)
• what the user expects to happen
• where (the place) the drug is used
• how it is taken
• whether the user is drinking alcohol or using other drugs

Some people feel nothing at all when they smoke marijuana. Others may feel relaxed or high. Sometimes marijuana makes users feel thirsty and very hungry"an effect called "the munchies."

Some users can get bad effects from marijuana. They may suffer sudden feelings of anxiety and have paranoid thoughts. This is more likely to happen when a more potent variety of marijuana is used.

What Are the Short-term Effects of Marijuana Use?

The short-term effects of marijuana include:

• problems with memory and learning
• distorted perception (sights, sounds, time, touch)
• distorted perception (sights, sounds, time, touch)
• distorted perception (sights, sounds, time, touch)
• increased heart rate

These effects are even greater when other drugs are mixed with the marijuana; and users do not always know what drugs are given to them.

Does Marijuana Affect School, Sports, or Other Activities?

It can. Marijuana affects memory, judgment and perception. The drug can make you mess up in school, in sports or clubs, or with your friends. If you're high on marijuana, you are more likely to make stupid mistakes that could embarrass or even hurt you. If you use marijuana a lot, you could start to lose interest in how you look and how you're getting along at school or work.

Athletes could find their performance is off; timing, movements, and coordination are all affected by THC. Also, since marijuana can affect judgment and decision making, its use can lead to risky sexual behavior, resulting in exposure to sexually transmitted diseases like HIV, the virus that causes AIDS.

What Are the Long-term Effects of Marijuana Use?

Findings so far show that regular use of marijuana or THC may play a role in some kinds of cancer and in problems with the respiratory and immune systems.

Cancer
It's hard to know for sure whether regular marijuana use causes cancer. But it is known that marijuana contains some of the same, and sometimes even more, of the cancer-causing chemicals found in tobacco smoke. Studies show that someone who smokes five joints per day may be taking in as many cancer-causing chemicals as someone who smokes a full pack of cigarettes every day.

Lungs and airways
Lungs and airways"People who smoke marijuana often develop the same kinds of breathing problems that cigarette smokers have: coughing and wheezing. They tend to have more chest colds than nonusers. They are also at greater risk of getting lung infections like pneumonia.

Immune system
Animal studies have found that THC can damage the cells and tissues in the body that help protect against disease. When the immune cells are weakened you are more likely to get sick.

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