NIDA for Teens: The Science Behind Drug Abuse
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Drug Facts Chat Day: Marijuana

Can someone overdose on marijuana?

If you mean can they overdose and die from marijuana—the answer is no, its not very likely. But they can experience extreme anxiety (panic attacks) or psychotic reactions (where they lose touch with reality and may become paranoid). And people can and do injure themselves because of marijuana's effects on judgment, perception, and coordination. For example, marijuana affect the skills you need to drive (e.g., concentration, reaction time) so people can injure themselves and others if they drive while under the influence. For more information on marijuana, see: http://www.drugabuse.gov/publications/research-reports/marijuana-abuse.

I thought marijuana was all-natural, how can it hurt your body if it's natural?

Many drugs of abuse come from plants, and therefore can be considered "natural." For example, heroin comes from poppy plants and cocaine comes from the coca plant. That doesn't mean they are healthy—think tobacco. Similarly, marijuana comes from a plant that contains THC, which is "psychoactive" (it affects mood and behavior) and can be addictive. For more information on mariijuana see http://teens.drugabuse.gov/drug-facts/marijuana and http://www.drugabuse.gov/publications/marijuana-facts-teens.

There are kids in my school who smoke pot and they seem okay. What is the big deal?

Marijuana, like most other drugs, affects the parts of the brain that allow us to make plans, solve problems, and make decisions. This is especially risky for teens, whose brains are still developing. So although these kids might seem okay now, they are changing their brain chemistry in ways that can have both short-term and long-term effects. 

In the short term—they run the risk of doing something dangerous when they are high—like driving and getting into an accident, not studying and having their grades drop, or seeing their athletic performance decline and getting kicked off a team. In the long term—smoking marijuana can cause long-lasting changes in the brain's reward system and critical brain regions involved in learning and memory. A recent study that looked at people for more than 25 years shows that smoking marijuana during the teen years can actually lower a person’s IQ by an average of 8 points, even if the person stops smoking marijuana as an adult. This means if you are a person with an IQ in the 50th percentile, your IQ would drop to the 29th percentile—a significant drop. This effect would not show up right away. Clearly, making decisions now to keep your brain healthy will help you throughout your life. 

Also, in the longer term, teens who start smoking marijuana risk becoming addicted. So don't believe just what you see on the outside--some of these changes take time to happen, and some people are more vulnerable to problems associated with drug abuse than others. We don't know all the reasons why, but genetics and a host of other factors--age of first use, other mental health problems, stress, family difficulties, peers that use drugs—all contribute to someone's likelihood of becoming addicted or developing other health problems because of repeated drug use.

You can read more about marijuana at http://www.drugabuse.gov/publications/marijuana-facts-teens or http://teens.drugabuse.gov/drug-facts/marijuana.

I've been smoking pot for 7 years. For 4 of those years I smoked every day. I quit smoking for about 3 weeks but everything I do now seems boring without weed. Is there anything you can suggest for me?

What you describe sounds like a no-win situation: life with weed or a boring life. But in fact, there is a way out. It is just hard for you to see it now, because it sounds like you are addicted to marijuana. Most people don't even realize that you can get addicted to it, but one of the hallmark features of any addiction is that not only does the drug itself become less reinforcing than it used to be (i.e., you need more to get the same effect), but so do most things in life that used to make you happy. In addition, someone who smokes marijuana daily is likely to experience withdrawal symptoms when they stop. For marijuana, this can include irritability, loss of appetite, difficulty sleeping, and mood swings. These can last for several weeks after you stop taking the drug. But, the situation does improve if you can stay off of the drug.

Here's my suggestion: Talk with someone who can help you get the help you need. If you can, talk to your parents. If you can't talk to your parents, then try a school counselor or another trusted adult and tell them that you'd like to get professional help. You can also call 1-800-662-HELP to find out where to get treatment. Or, you can call a hotline, like 1-800-272-TALK just to talk. Whatever you choose, you should know that life without drugs doesn't have to be boring - it can be interesting, happy and fulfilling. And you should also know that there ARE effective treatments available.

You should be proud of yourself for deciding and having been able to quit for 3 weeks (that is a hard thing to do for people that are addicted to any drug, and it is a very good start!). But going 3 weeks without weed (after 7 years with it) is not enough time for your system to recover so that you can feel how good life can be when you are free of the influence of the drug. You've taken a good first step and I encourage you to build on it in spite of the sure to come ups and downs.

Is marijuana really addictive?

Yes, marijuana can be addictive. For adults, one in nine marijuana users become addicted. However, for teens, that number becomes one in six. If you smoke it every day, your risk of addiction becomes 25% to 50%. That’s a big risk. Repeated use of marijuana or any drug changes the brain (and the body), making it hard for some people to quit. Many people do not believe marijuana can be addictive because the withdrawal symptoms are more subtle than those for other drugs like heroin, which has extremely uncomfortable withdrawal. People who are addicted to marijuana and suddenly try to stop are likely to experience irritability and restlessness. Many people do not recognize this as withdrawal.

Interestingly, one of our researchers surveyed people that had used marijuana regularly for many years. The marijuana users reported diminished life satisfaction and more physical and mental health problems, which they blamed on the marijuana. They also had poorer academic and job outcomes and lower salaries than a group of adults from comparable backgrounds who did not smoke marijuana.

Have most teens tried marijuana at least once?

Although it may seem that everyone smokes marijuana, that's not the case. In fact, a majority of teens do not use. In a national school survey of more than 10,000 kids last year, about 17% of 8th graders, 36% of 10th graders, and 46% of 12th graders reported having used marijuana at least once in their lifetime.

What are the long-term effects of smoking marijuana?

Using marijuana can produce adverse physical, mental, emotional, and behavioral changes, and, contrary to popular belief, it can be addictive. Chronic or long-term exposure to marijuana smoke, just like cigarette smoke, can harm the lungs. The use of marijuana can impair short-term memory, verbal skills, and judgment, and can also distort perception. Not surprisingly, students who regularly smoke marijuana get lower grades and are less likely to graduate from high school, compared with their nonsmoking peers. In addition, marijuana has been associated with a number of mental conditions, including schizophrenia (psychosis), depression, anxiety although we do not know yet whether marijuana can cause mental illness, particularly in healthy people who are not otherwise vulnerable to these disorders. There is good news, however, since there is evidence that if an individual quits marijuana, even after long-term or heavy use, their cognitive abilities (learning, memory) can recover.

For more information on marijuana, see: http://www.drugabuse.gov/publications/research-reports/marijuana-abuse

Does marijuana affect your ability to drive?

Yes. Studies show that 10 to 22 percent of drivers involved in vehicle crashes, used drugs often in combination with alcohol. In fact, we know that a moderate dose of marijuana can impair driving performance (i.e., reaction time, visual search frequency—driver checking side streets—or perceiving/responding to changes in speed of other vehicles); and that even a low dose of marijuana combined with alcohol markedly increased driving impairment over either drug alone.

You might find some interesting information on this very issue at: http://www.drugabuse.gov/publications/drugfacts/drugged-driving

Can marijuana be used as a medicine?

You have probably been hearing a lot about this since some U.S. states have voted to let adults use marijuana to help with some medical conditions. However, it is important to remember that the Government agency that keeps our food and medicine safe—the Food and Drug Administration (FDA)—has not approved marijuana to treat any medical illness. That is because not a lot of research has shown that smoking marijuana has medical benefits that exceed its risks—the same standard used to approve any medication. However, the FDA has approved certain medications that contain ingredients found in marijuana. These medications are usually prescribed to relieve symptoms in seriously ill patients, such as reducing nausea for people undergoing chemotherapy for cancer or helping people living with AIDS to eat more. Also, there is some new and exciting research looking at the biology of cannabinoids, the general class of molecules related to THC, the active ingredient in marijuana. With this research, scientists are hoping to find new ways of treating pain and other illnesses without the dangers of becoming addicted and without the health problems linked to smoking marijuana. It is also important to remember that no states have approved smoking “medical” marijuana for people under the age of 18—because it can cause problems with the developing brain.

See http://www.drugabuse.gov/publications/marijuana-facts-teens for more information.

Is smoking marijuana more harmful than smoking cigarettes?

Unfortunately, the answer is not so simple. On one hand, it is true that marijuana tar contains about 50% higher concentration of chemicals linked to lung cancer, compared with tobacco tar, and that smoking marijuana deposits four times more tar in the lungs than smoking an equivalent amount of tobacco. This is because marijuana smokers hold the smoke in their lungs longer than tobacco smokers do, allowing more time for extra fine particles to be deposited in the lungs. As a result, the lungs of marijuana smokers show some of the same pre-cancerous changes as the lungs of tobacco smokers, and marijuana smokers suffer some of the same respiratory problems as cigarette smokers—i.e., chronic cough, bronchitis, etc. Despite this, the verdict is still out on whether smoking marijuana increases the risk of developing lung cancer later in life. In a way this paradoxical observation illustrates why it would be ill advised to rank different drugs with respect to their differential ability to cause health problems. This is because there are many factors, some of which are drug-specific, and some which are biological, developmental, or even environmental that can contribute to the net effect of abusing any given substance.

I can tell you however, that both the nicotine in tobacco and the THC in cannabis are addictive and that the smoke you inhale from both is bad for your lungs. The smoke in cigarettes, made from either tobacco or marijuana, contains literally thousands of compounds, many of which are toxic.

For more information about smoking, go to: http://www.drugabuse.gov/drugs-abuse/tobacco-addiction-nicotine For more information about marijuana, go to http://www.drugabuse.gov/drugs-abuse/marijuana