These questions were answered by more than 50 individual scientists and science writers with expertise in addiction. To get as many answered as possible, responses were written quickly based on the personal background and knowledge of each expert. Please note that there was not a secondary review or proofreading of each fact, and if readers have questions or comments about any response, they can ask further questions.

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what does thc stand for


THC stands for tetrahydrocannabinol and is one of hundreds of chemicals in marijuana.For more information about marijuana, go to

-Steve Gust



Weed is marijuana.Marijuana is the most commonly used illegal drug in the U.S. Nearly 45% of teenagers try marijuana before finishing high school. It can be addictive, and can affect learning and memory, which is not good if you're trying to do well in school.Marijuana can also cause cancers associated with using inhalants. For more information see

-David Shurtleff

what drug do you feel is most addictive physically

-Health Class,

This question is hard to answer precisely. There is a lot we still don't know about who becomes addicted, why, and after how much drug exposure. We do know that each person is different with different vulnerabilities to drugs, so it'shard to predict a drug's effects on an individual. It's a little like playing "Russian Roulette" -- if you choose to use drugs. But, if you do, the earlier you stop, the more likely you will be to avoid addiction and the harmful brain changes that lead to it. For more information, see Hope this helps, and thanks for the good question.

-Joe Frascella

What drug is most dangerous?


That's a good question. All drugs can be potentially dangerous. It depends on lots of factors, especially since there is still a lot that we don't know about who becomes addicted and why. We do know that each individual is different, so it is really difficult to determine why one person may have one reaction, and another may have a more severe reaction. Here is a source of free information about the latest science-based drug abuse facts, publications, and teaching materials for parents, teachers and students.

-Joe Frascella

what drug is the most commonly used illegal drug among middle school and high school students?


The most commonly used 'illegal' drug is marijuana. However, that's only if you don't count alcohol--which is illegal for middle school and high school students because they are underaged.

-Aria Crump

What drug is the worst one for you and has the highest mortality rate?

-Tractor Trailer,

Great question - I suspect you are a potential scientist! We have found all drugs can cause medical, psychological and social problems. As a doctor, I've seen people with terrible trouble quitting their use of marijuana, even though it was causing them a lot of trouble. I have also worked with patients who abused heroin and cocaine who quit using the first time they tried. On average, tobacco smoking (cigarettes) cause the most deaths around the world. For additional information, check out:

-Wilson Compton

What drugs affect many different parts of your body? For example, some drugs only affect one place of your body....which drugs will be effecting your whole body?


all drugs are distributed to all the body and thus all drugs in principle can affect more than your brain. for example, alcohol affects brain and liver. cocaine affects brain and heart. nicotine affects brain, lung and heart. And marijuana affects brain and lungs. You can find out more about that at:

-Nora Volkow

What drugs are most likely to kill you?


all drugs can kill in various ways. their lethal effects will depend on doses, combinations and a person's unique genetics. the drugs that are most frequently associated with death are heroin because of respiratory depression from overdose, alcohol from intoxication and increases in car accidents, and cigarettes from lung and other cancers

-Nora Volkow

what drugs can stunt your growth


Abusing steroids (the so called, androgenic anabolic steroids) can cause you not to reach your intended height because they send early signals to the bones to stop growing. Some stimulants have also been reported to stunt growth.

-Barry Hoffer

What drugs have addictive properties


All drugs are potentially harmful and may have life-threatening consequences associated with their abuse.These include amphetamines (or speed), opiates such as heroin,cocaine, PCP, tranquilizers, marijuana, smokeless tobacco products, and cigarettes. How quickly you might become addicted to a drug depends on many factors including the biology of your body.There are also vast differences among individuals in sensitivity to various drugs. While one person may use a drug one or many times and suffer no ill effects, another person may be particularly vulnerable and overdose with first use. There is no way of knowing in advance how someone may react. To learn more, check out "The Science of Addiction" at

-Frank Vocci

what drugs make you commit scuiside


Thanks for your question. The main issue to keep in mind is that all drugs can affect someone's mood. Some drugs cause people to make very bad decisions, including wanting to kill themselves. Working in an emergency room as a doctor, I often took care of people who attempted suicide while they were drunk or high on many different substances. Almost always, when the person sobered up, they didn't feel so bad and didn't want to die.If you are concerned about someone and want to help him/her, please let them know that treatment is available and can be found at the Substance Abuse Treatment Facility Locator at 1-800-662-HELP or go to their website at

-Wilson Compton

what effects do vicadin have on the body??


Its is an opiate analgesic so it can decrease pain. However it can also make a person feel high and with repeated use can produce addiction. For more information:

-Nora Volkow

what exactly is dopamine?


Dopamine is a neurotransmitter similar to adrenaline. Dopamine is connected to the thought process, it affects a person's movement, emotional response, and the capacity to feel pleasure and pain. Shortages or Excessive Dopamine levels can impair your ability to think clearly, to remember things, or to control muscle movements, and can also affect your personality in many different ways. Drugs of abuse increase the release of dopamine in the brain's reward centers. With continued use and release of dopamine, individuals can become addicted to this effect and start to take the drug without even thinking about it. With continued use, drugs of abuse can affect decision making and affect your ability to learn new things. Eventually, the drugs can mess with your brain so much that you can lose control of your life.

-Joni Rutter

What happens when you overdose on heroin ?


It causes you to stop breathing.Death can occur within minutes after you stop breathing. It is important to call 911 and get emergency medical help as quickly as possible.

-Frank Vocci

what happens when you overdose?


it depends on what drug you overdose on. if you overdose on heroin or alcohol your respiratory centers in your brain stop working and that is why people die. if you overdose on cocaine or amphetamine you can develop a severe seizure that can kill the person.

-Nora Volkow

What happens when you take an overdose of ADHD meddication?


it can make you paranoid, it can produce seizures, it can also produce heart arrhythmias

-Nora Volkow

What helps to cure your drug habbits?


Drug treatment is the best way. getting involved in non drug related activities will help a person cut down their drug use. For more on treatment and where you can find it, you can call the go to the Substance Abuse Treatment Facility Locator at 1-800-662-HELP or go to their website at

-Nora Volkow

What in drugs gets your adrenaline pumping?


Many drugs known as "psychostimulants" such as cocaine and methamphetamine can lead to increased heart rate and blood pressure, which are related to the effects of adrenaline. You can find out more about that at:

-David Shurtleff

What in methamphetamine makes it so addictive and dangerous?

-Coolio The Great IIV,

Methamphetamine is so addictive because it sticks around in the body for such a long time, so it has a much stronger effect than other stimulants. To learn more, check out "The Science of Addiction" at

-Steve Grant

what is a drug


That's a great question. A drug is a substance that you put into your body to have a certain effect. For example, some drugs are medicines and you would take them to improve your health. Other kinds of drugs are taken because the person thinks they will change their behavior or make them feel better. Some of these are legal, like alcohol and tobacco, and others, like cocaine and marijuana, are not. The drugs in the last two categories can have seriously bad effects on people who use them. You can find out more about that at:

-Nancy Pilotte

What is a good way to tell someone that they have a drug-related problem?


One of the best ways to tell is if the person seems obsessed with the drug, using more often than they intended and spending more time recovering from the drug use than planned. Also, continuing to use the drug even in the face of medical or mental problems or despite damaging consequences, such as loss of job, home, and support of friends and family.To learn more, check out "The Science of Addiction" at

-Frank Vocci

What is in Rohypnol that will make you lose your memory?


rohypnol is a benzodiazepine used for anxiety and insomnia that can interfere with your memory as do other drugs in that class. this is because the proteins affected by them interfere with activity in hippocampus which is were memories are formed in the brain

-Nora Volkow

what is it about cigarettes that get people addicted??

-hey hey hey,

The tobacco leaf contains a chemical called nicotine, which is one of the most addictive substances we know of. Because of the large surface area of the lungs, smoking cigarettes is an extremely effective way of delivering nicotine to your brain, where it can activate many of the same brain circuits as other addictive drugs. For more information about smoking, go to:

-Barry Hoffer

What is ketamine,rohypnol,and gamma hydoxybutyrate?

-grand theft auto master,

Ketamine, rohypnol and gamma hydroxybutyrate are drugs that are sometimes called "club drugs" because they are often used in nightclubs, bars, or raves. Ketamine is actually an anesthetic that is most commonly used in veterinary medicine. Ketamine is also known as "special K" or "vitamin K".Rohypnol belongs to a class of drugs known as benzodiazepines. When Rohypnol is mixed with alcohol it can prevent a person from resisting sexual assault. It can also cause someone not to remember events they experienced while under the effects of the drug.Rohypnol is sometimes called"rophies," "roofies," "roach," and "rope. "Gamma hydroxybutyrate is a central nervous system depressant that is sometimes called "liquid ecstasy," "soap," "easy lay," "vita-G," and "Georgia home boy." GHB can cause coma and seizures and combining GHB with other drugs can result in nausea and breathing difficulties. You can find lots of information about club drugs at

-Larry Stanford

what is the average percentage of teens that use drugs in the US?


According to the Monitoring the Future study 48.2% of 12th graders, 36.1% of 10th graders and 20.9% of 8th graders have used drugs at some time in their life.

-Wilson Compton

what is the average perentage that people use and do drugs around the whole world?


Drugs are abused by people in all countries of the world.The particular drugs that people abuse tend to be the ones that are available close to where they live, although the drug smugglers are very good at making many different drugs available. Without a doubt, marijuana is the most prevalent drug used around the world. If you would like additional information on patterns of drug use in other countries, look at the website

-Steve Gust

What is the best way to break the addiction to drugs?


The best way to break the addiction to drugs is to get help from a doctor or therapist or support group. For more on treatment and where you can find it, you can call the Substance Abuse Treatment Facility Locator at 1-800-662-HELP or go to their website at

-Melissa Riddle

What is the best way to get someone to stop smoking?


There is no single best way to stop smoking. Most of the research suggests that every person is different and will need a plan that is tailored to their need. There is lots of help available through the National Cancer Institute ( and the National Cancer Association ( I encourage you to check these sites for some specific advice that might help you or a friend.

-Steve Gust

What is the deffinition of being addicted to a drug?


Thanks for the great question! Addiction is a chronic, often relapsing brain disease that causes compulsive drug seeking and use despite harmful consequences to the individual that is addicted and to those around them. Drug addiction is a brain disease because the abuse of drugs leads to changes in the structure and function of the brain. Although it is true that for most people the initial decision to take drugs is voluntary, over time the changes in the brain caused by repeated drug abuse can affect a person's self control and ability to make sound decisions, and at the same time send intense impulses to take drugs. It is because of these changes in the brain that it is so challenging for a person who is addicted to stop abusing drugs. If you would like more information on the topic, you might check out:

-Joe Frascella

what is the difference between cocaine and crack???????


Great question. The major difference between cocaine and crack is how they are taken. But both drugs are a form of cocaine. Cocaine is the powdered form, usually the hydrochloride salt, of the drug.Crack is the free base form (and you thought that chemistry class was useless!).

-Nancy Pilotte