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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Does cigarette smoke give you cancer?

-Jimmy John Jr, Illinois

Hi Jimmy John Jr,
Cigarette smoke contains a toxic mix of 7,000+ chemicals, including more than 70 that can cause cancer. In fact every cigarette smoked increases the risk for cancer.
Find out more facts about cancer and smoking by visiting:

-Suzanne Lim

Does Coca Cola have trace amounts of cocaine in it?

-Superdood, Illinois

Hi superdood.
It used to in the olden days but not any longer

-Emily Einstein

Do you believe marijuana should be Legal?

-#VapeNation, Illinois

Hi -- Since the legalization of marijuana will lead to increased use and the problems that go along with that, NIDA hopes that good science will inform decisions about legalization. Whatever happens, we do not want more teens to use marijuana, because of the potential impact on the developing brain (whcih does not stop developing until you are in your mid-20s.) For more information on the negative effects of marijuana, see our booklet, Marijuana: Facts for Teens:

-Steve Gust

Do you believe Marijuana should be used for medical purposes?

-Chungus, Illinois

There has been a lot in the news lately about medical marijuana. While the marijuana plant has not been approved by the FDA for the treatment of any medical condition, there is early research suggesting that some of compounds in marijuana may potentially help treat things like epilepsy, cancer, obesity, or addiction. Scientists are studying these ingredients to try to develop new medications. A pill form of THC (an active ingredient in marijuana) is already available for certain conditions, such as nausea associated with cancer chemotherapy and weight loss in patients with AIDS. Smoked marijuana isn't an ideal medication due to its negative health effects, including the risk of addiction and the damage that smoking can do to the lungs.

-Tisha Wiley

do you guys feel using scare tactics is the best way to prevent kids from using drugs ya yeet

-dash, Illinois

Hi Dash--I perfer being honest. For instance, we know that the earlier that kids try drugs, the more likely they are to become addicted. we also don't know the long-term ways drugs can affect the growing brain and if you can recover from these changes. You get only 1 shot a growing a FABULOUS brain--why risk it? I should also mention that just knowing the facts and that drugs are harmful might not prevent people from using drugs, so we recommend creating a positive environment for yourself (by cultivating an awesome support network of family and friends) so that you don't go down that road. Here is a link to learn more about preventing drug abuse: Thanks for the great question!

-Ruben Baler

do tactile drugs exist


Hi Maite,
Several recreational drugs such as cocaine, amphetamines, narcotics and (more famously) magic mushrooms have been reported to cause tactile hallucinations (the false perception of tactile sensory input that creates a hallucinatory sensation of physical contact with an imaginary object). These types of hallucinations can also be caused by neurologic disorders like Schizophrenia, Parkinson's disease, and Alzheimer's disease.
Thanks for the great question. Respect your brain and stay healthy.

-Ruben Baler

DO teens smoke more in high school or in college

-Angela-FVSU4H, Georgia

Hi Angela! About 9 out of 10 cigarette smokers first tried smoking by age 18, and 98% first tried smoking by age 26 so both high school and college as prime times where smoking starts. More Information about smoking and prevention can be found at

-Steve Grant

do the people who play video games produce the same brainn waves as when someone is using cocaine.

-SB, Montana

hi s b
good question.
Brain waves could be useful but may not be all that informative in this context. Dopamine on the other hand tells a more interesting story: the dopamine releases people display in their brain reward centers during video gaming or online social interactions can be very similar to those that happen in the course of a drug experience. This is one of the reasons we think that some video games could be actually quite addictive.
Thanks for your interest.
best of luck

-Ruben Baler

Do u get worse when combining different types of alcohol

-romina ,

Thank you for your question! All of the forms of alcoholic beverages that people drink contain a type of alcohol called ethanol. It's the only type of alcohol that is even remotely safe to drink.
In terms of the different types of beverages -- wine, beer, distilled spirits -- they all contain the same drug, ethanol. Whether a person drinks beer, wine, spirits or all of the above, they're taking the same drug. It's not the combination, it's the amount of alcohol that causes harm.

-Heather Kimmel

hello my name is barnacle boy what are the long term effects on vaping thank you have a great day buddy

-Xxtacticalman, Washington

hi there barnacle boy -
You bring up a great question. Vaping is fairly new, so we don't really know the long term effects yet. However, at this point, it looks like vaping leads to nicotine addiction. Addiction means that people cannot stop using the drug, and this can be problematic. Some people who vape end up smoking too. A lot of people are studying the effects of vaping, so stay tuned! Thanks for asking a question today!

-Michelle Leff

hello when someone tried to get me to vape of course I said no to the kid but i thought why would he try to get me addicted the question I have for you is why do people try to get others to vape and do drugs

-CP, Illinois

Thanks for your question C. People are social beings. We tend to want to do things with others.The most improtant thing is trying to stay true to who you are and feel comforatble with your decisions. Keep making positive healthy choices and surrond yourself with friends that support you. To learn more about tobacco, nicotine and e-cigs, see

-Aria Crump

Hello Which are the worst consequences of drug use?


Hi there - unfortunately the worst consequence of drug use can be death. There really is no safe drug use unless you follow your doctor's directions.

-Michele Rankin

Hello! How likely is it to get addicted to marijuana and how often would you have to use marijuana to become addicted?

-mb, Illinois

Hello! Up to 9 percent of people that try marijuana get addicted to it. In addition, if you're less than 18 years old, your risk is higher, up to 17 percent. Here's more information so you can draw your own conclusions:

-Anto Bonci

Hello, how can i help a friend that consumes a drog?


Hi MU- Thanks for your question. It is important for you to help them in any way you can. You can help them get the facts and understand the harmful effects of smoking marijuana like long terms problems with learning and memory, anxiety and smoking related cough and breathing problems. But, maybe the most important way is to help them is just by giving them encouragment and being a good friend. Here's a link with some more information:

-Kris Bough

Hello, how can i help a friend that has been dealing with drugs???

-its me,

Hi its me. It's really tough when someone you care about is dealing with a drug problem. Your friend may or may not realize that their drug use is causing harm--and he or she may not realize until the problem grows worse. As a friend, you can set a good example and encourage your friend to spend time with people who don't support the use of drugs. Depending on the situation, this may not be enough and your friends best chance may be to connect with a professional. You're a good friend--keep up the good work! Here are some resources for getting help with a drug problem: call 1-800-662-HELP, 24/7. Or you can go to to find information about treatment centers in your area.

-Aria Crump

Hello, I am a teacher asking my students' questions: Why are some drugs legal and illegal? What are their classifications?

-Miss Vins Class, Illinois

The Drug Enforcement Administration (DEA) is the lead agency responsible for classifying drugs which is based on various factors about their safety and use. Here's their website:


-Dave Thomas

Hello, I am considering taking stimulants to up my fortnite game. Are there any negative side effects to this?

-EpicGamer10001, Maryland

Hi EpicGamer10001 - There are negative side effects to using stimulants in this situation. One thing is that your sleep-wake cycle could be disrupted. The second is that you may become addicted to stimulants - they are highly addictive. And finally, when under the influence of many drugs (including stimulants) your ability to think and your coordination can be affected - so it may affect your fortnite game in a bad way!

-Michelle Leff

Hello, I am from Mexico Do some of the medicines for mental health have drugs?


I wonder if you're asking two different questions. (1) Is there evidence that illicit drugs might help people with mental illness? The answer to this is not really. While some people are doing research to find out whether some illicit drugs might be useful for people with mental illnesses, there are no definitive studies demonstrating that they work -- and there are lots of great treatments that do work. (2) Are some meds used to treat mental illnesses also drugs of abuse? Here the answer is yes -- some people do abuse medications, and this can be dangerous.

-Joshua Gordon

Hello, i am from Mexico, where it is unfortunately common for girls to get raped or for people to be kidnapped by being drugged. How do you know if a drink is adultered?


Hello mj,
You bring up a very serious issue. There is no reliable way to know if someone has spiked your drink with alcohol. Sometimes, adding alcohol can change the taste or smell of the drink, but in many cases you can never be sure. One way to help prevent getting an altered drink is to not accept anything from someone you don't know or trust. Also remember, in the U.S., it is not legal for children and teenagers under 21 to drink alcohol, and in many countries, it is also illegal to serve alcohol to minors.
Hope this helps!
- Vijay

-Vijay Ramchandani

Hello, Im from Mexico. What are the main consecuences in consumig a lot of drugs?


Hello! Thanks for writing in from Mexico. There are many consequences related to drug use (e.g., alcohol, tobacco, other drugs), such as effects on your health and development -- including brain development. Consuming large quantities of drugs can increase risk for overdose, too. Also, using drugs and alcohol can increase your risk for developing a substance use disorder, and there can be consequences on school performance and other areas of your life, like relationships with family and friends. Here is some additional information you may find helpful below.
Publication: The Teen Brain: 6 Things to Know
Video: Development of the Young Brain:
There is a lot of information about the health effects of drugs on NIDA's teen site here:
Hope this is helpful!

-Belinda Sims

Hey guys. I'm 16 and I've been severely caffeine addicted for over 3 years. My question is: Why do I still need sleep? Frankly, I'm both shocked and disappointed that my brain and body haven't adapted to run solely on coffee

-JustAPotato, Illinois

Hi Justapotato
Interesting question
You shouldn't be so disappointed. Sleeping is not extra, it's a basic unavoidable function, like eating or breathing. You need it to cleanse the brain from the daily debris. It is not an optional. Also, you are not addicted to caffeine (no one is), you are just caffeine dependent, try to cut down a little if you can.
best of luck

-Roger Sorensen

Hey rueben! If all my friends are into smoking, should I do it too?

-chamness_a, Oregon

HI Chamness
I think you can actually do an interesting experiment here, in your situation:
1) Think hard what it is that YOU want to do (re: smoking).
2) If smoking is what you WANT to do, then there is no problem (except for your brain and your lungs)
3) If you are not interested in smoking then just don't.
4) Keep an eye on how your friends react to YOUR decision.
5) If they keep doing their thing and don't care about your smoking or not, that's cool.
6) But if they exert any pressure for you to become a smoker like them, maybe they are not friends worth keeping.
best luck to you.

-Ruben Baler

Hey thanks for taking the time to answer. I once heard that the more you use a drug the less it "hits you after". Does it apply to all drugs, even medicine.


Hey Farkas! That is both correct and incorrect. As people continue to use illicit drugs or misuse prescription drugs, they typically need higher doses to experience the experiences they originally sought from the drug. At the same time, the unpleasant symptoms of withdrawal can get worse, so that quitting becomes harder. This is not true, though, of most medicines


-Anto Bonci

Hey there, I was wondering if eating cocaine has any major effects on your body, and why.

-tommy, Montana

Hi tommy - Ingesting (eating) cocaine will result in the same effects as if taken by other routes of administration (click on this link for more on effects- But, typically, when ingested this way, it takes longer for the drug to reach the brain as it must be absorbed into the bloodstream from the stomach and digestive system. You will still receive the stimulant effects of the drug, but these might be longer lasting. However, it can be an irritant to your system.

-Roger Sorensen

Hey, is there a reason that weed is safer than cocaine and heroin even though they are both grown from plants?

-Evan4477, Illinois

Many things are derived from plants - some useful, some toxic. I wouldn't say that weed is safe, as chronic use can lead to a number of undesired consequences, especially with respect to school performance. But certainly, cocaine and heroin are much more dangerous because in addition to their effects on the brain and higher addiction potential, these drugs damage other organs in the body like the heart and liver, and overdoses can be fatal.

-Steve Grant

Hey, whats worse, cigarettes or vape with a really low percentage of nicotine?


Hi blue,
Studies are being done to determine the potential effects of e-cigarettes. Research has found that youth who use a tobacco product, such as e-cigarettes, are more likely to go on to use other tobacco products, such as cigarettes. Right now, we don't know how many harmful or potentially harmful chemicals are in e-cigarettes. Because e-cigarettes were not regulated until recently, labels that say they are nicotine-free may not be accurate. Bottom line is: there are no safe tobacco products. You can learn more information about how to stay tobacco-free by checking out

-Ruben Baler

hi dr dave s pot a good pain killer

-kermit the frog, Illinois

Hi, Kermit the frog. Some researchers have reported that cannabis has analgesic (pain killing) effects, but cannabis is not always effective long term to treat pain, nor is it a FDA-approved option. Please consult your doctor for safe and effective pain treatments.

-Dave Thomas

Hi i waned to know what makes alcohol and drugs so adictive for people, why isn't it easy to stop drinking when you are adicted to it


Hi Doina,
Thanks for a great question!
Alcohol is like most other addictive drugs.It causes the release of the neurotransmitter dopamine in the brain's reward area, which is what causes the pleasurable sensation (the high). After repeated drug use, the brain starts to adjust to the surges of dopamine. Brain cells (neurons) make less dopamine receptors or simply make less dopamine. The result is less dopamine in the brain—like turning down the volume on the reward signal. This can mean that the person starts to consume more alcohol leading to addiction. Ultimately, alcohol use can eventually lead to dramatic changes in neurons and brain circuits, which result in addiction. Learn more at: And on this link to find out how drugs affect your body:

For more info on the science of addiction google Drugs, Brains and Behavior-The Science ofAddiction. />- Vijay

-Vijay Ramchandani

hi my doubt is that if you consme drugs does it affect your reproducting system?


Hi El,
Yes, some drugs do impact the reproductive system. For example, steriods can have a profound effect. For more on steriods, check this out:
for more on this, for more info on steroids, and check out Ruben's video:

-Dave Thomas

Hi what are the most common medicinal drugs ?

-Mateo ,

Not sure Mateo.
I know more about the misuse of drugs and alcohol. The most common substance used by teens is alcohol. Roughly 30 percent of high school seniors reported using alcohol in the past month. The most common illicit drug used by teens is marijuana. Both alcohol and marijuana can have negative effects on teenage brains that are still developing, especially when they are used heavily or often, so that's a big concern. Here are the latest rates of teen drug use from our Monitoring the Future Survey (of 8th, 10th and 12th graders):

-Dave Thomas