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 here.

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why is weed bad because somebody told me that it just relieves stress

-Archie C, Texas

Actually marijuana, or at least some of the chemicals in it, may have some value as medicines. The problem is we don't know exactly when they help people, and when they really don't do much of anything. That is why we are doing research to help answer these research questions and others. In fact I just did a video answer to Molly's on this question. Wonder if you saw me? take a look at this:

-Dave Thomas

Why is weed or cannabis considered addicting even tho the drug itself contains no addicting substances now ik that most doctors would blame the human mind but i think that the issue deals with chemicals being applied to the plant due to noncontrolled enviorments what do you think

-l, Nebraska

Marijuana has a drug in it called tetrahydrocannabinol, or THC, which is addictive. Here is some more info that might be interesting:;

-Steve Gust

why isn't drinking illegal

-@!?!, Texas

Well, it is illegal for people under 21. And it's not legal for adults to drive after drinking too much. Aside from these circumstances, many adults can drink and enjoy moderate amounts of alcohol in ways that do not increase their risks for harm.

-Aaron White

Why isn't drugs banned

-Angelica@Gentry, Texas

Hi Angelica,
Most drugs are banned (illegal). The only exceptions are alcohol and nicotine (in cigarettes and e-cigs), and in a growing number of states, marijuana.

-Eric Wargo

why isn't marijuana a safe medicine

-danielleFVSU4_H, Georgia

Lots of reasons--it hasn't been tested for most conditions for which it people are using it. Also, we would never prescribe any other medication without knowing what the proper dosage is, what is in it (the marijuana plant varies widely in its ingredients), without guidelines that physicians could use to prescribe it, and certainly we would not want a medicine that is smoked. That said, we think there is lots of potential for developing medications based on some of marijuana's components; and scientists are actively working on this. ,

-Susan Weiss

Why isn't smoked marijuana a safe medicine

-jada fvsu 4h, Georgia

Lots of reasons--it hasn't been tested for most conditions for which it is being used. Also, we don't prescribe medicines without knowing what the proper dosage is, what is in it (the marijuana plant varies widely in its ingredients), without guidelines that physicians could use to prescribe it, and certainly we would not want a medicine that is smoked. That said, we think there is lots of potential for developing medications based on some of marijuana's components; and scientists are actively working on this. ,

-Susan Weiss

why marijuana is medicinal ?

-adv, Other

Hi adv - marijuana has not been approved by the FDA to treat any medical condition, so it is technically not an approved medication. Research is underway to determine if some of the chemicals purified from marijuana can be used as medications, but more research is needed until they will be recognized as approved medications.

-Michele Rankin

Why the cigarrate is so addicted?

-CHF, Other

Cigarettes are very addictive for a few reasons. First, cigarettes contain nicotine -- the addictive chemical in tobacco. Second, cigarettes are specifically designed to maximize the addictiveness of nicotine. Third, inhaling nicotine in the lungs is a highly effective way of exposing the brain to nicotine. My advice -- avoid tobacco in all forms, but especially cigarettes!

-Kevin Conway

Why the drugs make you so vulnerable?

-AMC, Other

In addition to health affects, many drugs affect your cognitive abilities--particularly your judgement, and having solid judgement is important when you're with friends, at school, around your home, or even just crossing the street. Also, studies suggest that drug use can have an impact on teenagers' developing brain. Your brain is the control center for your entire body--so protecting it just makes sense.

-Aria Crump

why was meth first invented?

-slogan, New Hampshire

hey slogan, it was first invented in Japan in the early 1900's. It was used to keep soldiers awake during war.

-Maureen Boyle

why when people get depressed they take drugs?

-NCM, Other

Hi NCM--Sometimes folks who are depressed take drugs because they believe the drugs will make them feel better. But drugs will only make it harder to treat depression. Much better to seek out treatment by a health professional--there are effective treatments that can help people feel better.

-Charlotte Armstrong

why when weed dont get you high anymore people go to heroin or crack ?

-TrayxNaaa, Pennsylvania

Hi again TrayxNaaa - The body and brain adapt to repeated exposure to drugs by reducing the general response to them. This does mean that the same amount of a drug may have less of an effect than previously. While most people don't progress to heroin or crack, some of them do. It's certainly a worrisome sign.

-Wilson Compton

Why when you take drugs you have a high chance of getting addicted to it?

-Dinerbone, Illinois

There is a lot we still don’t know about who becomes addicted and why, and after how much drug exposure. We do know that each person is different, so 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.

-Michele Rankin

Will you become addicted to prescribed drugs?

-M.Guerra, Pennsylvania

Yes, people can be addicted to prescription drugs. For example, many people become addicted to prescription opioids. Just because they are prescribed by doctors does not mean they are always safe. Check out for some more good info.

-Dave Thomas

will you die if you mix drugs with alcohol.

-dtrach, New Hampshire

There are no real certainties when one mixes alcohol and other drugs, but mixing drugs and alcohol is very risky. For example, alcohol use is associated with an increased risk of opioid overdose. Drug and alcohol use is associated with car crashes and a lot of other bad outcomes.

-Dave Thomas

with all the different types of marijuana out on the streets and supposedly there are different types and effect is anyone aware of the additional make of marijuana

-danielleFVSU4_H, Georgia

Hi Danielle
There are a lot of different types of marijuana out there, but the key thing to remember is that they all have THC, or tetrahydrocannabinol, which is a powerful drug. Most of the different types are just for advertising and do not really represent any meaningful differences between types.

-Steve Gust

would you go to even more depression while using drugs

-vlam, Texas

Many drugs can indeed make you feel depressed -- some when you take them, some when they wear off. Some people may be more likely to get depressed than others when they use specific drugs.

-Josh Gordon

Y do ppl that take drugs supposedly need help if it's there choice?were do they go for help if that?

-Kaitlyn , Texas

Great Question! People use drugs for lots of different reasons, such as peer pressure, boredom, rebellion, curiosity, and so on. People can know drugs are bad for them, but they may still choose to take the risk, while others may not be aware of all the risks. Then, once they’re hooked, it can be very difficult to stop.

There are medications to help with some addictions including nicotine/tobacco, alcohol, and opioids (e.g. heroin or pain pills). And there are also behavioral therapies (counseling) to help people recover. But addiction is often a lasting condition, like heart disease or diabetes; there are treatments that help someone live a healthy, productive life but there is no cure. NIDA scientists are working hard to develop better treatments to treat addictions to all types of drugs. See our Step-by-Step Guides to learn how to get treatment:

-Michele Rankin

y does drugs make people be addicted? Is it the feeling of the drug that makes them want to smoke?

-Matthew G, Texas

Hey Matthew G- at first, people might take a drug for the feeling it gives them, but using drugs can cause changes to the brain over time that result in addiction. Frequently, someone who's addicted to a drug is taking it more to avoid withdrawal symptoms than to experience a high. The brain changes that cause addiction will cause someone to take drugs despite the negative consequences. Check out this website to find out more about the way that drugs affect our brains:

-Emily Einstein

yesterday i was put on laughing gas .... is that the same feeling as getting high ? could laghing gas kill you?

-rigsby, Texas

Hi Size,
Great question. Laughing gas is nitrous oxide, an inhalant that is sometimes abused to get high. It could definitely kill you -- that's why doctors are specially trained in how to give exactly the right amount.

-Eric Wargo

Yo, what up, Dave Thomas, What happens if someone takes too much of nicotine? Could this impact a teenager's future? Are they able to buy these drugs at a drug store near their location? -JArdsley, Ardsley High School

-JArdsley, New York

Its me!!! Dave Thomas. Not much up, just doing this chat day thing.

I am not a huge expert on nicotine, but we do have experts at NIDA on this. Here is a lot of useful information from NIDA:

-Dave Thomas

You know how people use MJ for medical purposes, but why do they take this substance to their own advantages and keep using it for bad things?

-pc, Indiana

Hi pc, thanks for this interesting question. In certain states, marijuana (MJ) is prescribed for medical purposes, such as for pain relief. When MJ is given to patients by a doctor, it can be used safely and effectively. Taking medical MJ is much different than taking MJ obtained from drug dealers or friends, which can be dangerous. Using MJ under any circumstances can be risky because the substance causes changes in brain function and problems with learning and memory. Finally, taking MJ can be habit-forming and lead to addiction. I've attached a web link with more information about MJ:

-Michael Baumann

\ how do drugs kill somone after a little time

-buldy 456 lohla, Colorado

hey buldy 456 lohla, some drugs like opioids (prescription pain relievers or heroin) kill people by stopping their breathing, other like stimulants (cocaine, methamphetamine) can kill people by causing cardiac arrest.

-Maureen Boyle