Note: There is no transcript for CHAT DAY 2018, which was cancelled due to the Government Shutdown initiated on January 20, 2018.

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.

You searched for tolerance and dependance and addiction. Showing 1 to 30 of 1996 questions.
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Can alcoholism and drug addiction be inherited?

-J_Blasian04, California

This is an important question. We know that genetics do affect people's risk for addiction. People who have a family history of drug or alcohol addiction are at greater risk. Environment is also very important--stress and other negative environmental factors can increase addiction risk, but having good friendships and family support can protect people who are at risk. Also having a stimulating environment, like having lots of hobbies and interests, can reduce your risk. The safest thing is to never try drugs.,

-Roger Little

Are alcoholism and drug addiction genetically inherited?

-4-H, Colorado

hey 4-H, yes genetic factors do play a role in addiction to drugs and alcohol. It is estimated that about half the risk is genetic and half environmental (social support, access to drugs, stress, etc.)

-Maureen Boyle

Are alcoholism and drug addiction genetically inherited?

-Amanda R., Texas

Dear Amanda R.,

This is a great question. We know that genetics do affect people's risk for addiction. People who have a family history of drug or alcohol addiction are at greater risk. Environment is also very important--stress and other negative environmental factors can increase addiction risk, but having good friendships and family support can protect people who are at risk. Also having a stimulating environment, like having lots of hobbies and interests, can reduce your risk. The safest thing is to never try drugs.,

-Roger Little

Are alcoholism and drug addiction genetically inherited?

-Molly Look, Colorado

People can inherit a susceptibility to become addicted to alcohol and drugs. But, inheriting that susceptibility doesn't mean that they automatically will become addicted. Having said that, if alcohol and drug addiction, including nicotine addiction, seems to run in someone's family, they would be wise to stay away from those drugs. Nobody can become addicted to a drug they don't ever use. Better to be safe than sorry, as many who have become addicted can tell you.

-Cora Lee Wetherington

what are the physical signs of abuse and addiction

-texas, Texas

Different drugs act differently; but in general, people who are addicted to a drug are less healthy and will look less alert or less healthy. Drugs all cause 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.This can mean that the person starts to find natural rewards – like food, relationships, or sex – less pleasurable, one of the signs of addiction. Some drugs are toxic to the brain and cause some brain cells to die. Drug use can eventually lead to dramatic changes in neurons and brain circuits, which result in addiction. Learn more at

-Michelle Leff

Why is marijuana criminalized but alcohol is not, when the affects of alcohol on your system are worse and the risk of addiction is so much higher? Why is alcohol not demonized the way it should be but so many other substances are?

-m1234, Illinois

this is an excellent (and i could add fascinating) question. Unfortunately the answer cannot be given from a scientific perspective. Your question really is a politico/cultural/social one, and thus lies outside the scope of what we can responsibly address.

-Ruben Baler

can some people be more prone to addiction and alcoholism?

-nikkinikkilo, Maryland

Yup, there is a certain portion of addiction that is genetically mediated. One is not born as a person with substance use disorder, but there are people that are more prone to addiction. The good news is that one can defeat this genetic predisposition by not starting!

-Dave Thomas

How can you avoid drug abuse and addiction?

-ssob17, Maryland

Hi ssob17,
Great question. The simple answer is don't do drugs -- you can't get addicted if you avoid taking them in the first place. But there are a lot of pressures on people your age to try drugs, so it can take a lot of strength and resolve to resist temptations. Once people do try them, it can be tempting for some people to take them again ... and then they are on the path to a possible drug problem.
Stay strong, and stay healthy! :-)

-Eric Wargo

can legal drugs like Prozac, help with drug addiction?

-janemiz, Rhode Island

There are some legal drugs that help with drug addiction. Prozac and other antidepressants are useful if someone has an addiction and also suffers from depression. There are other drugs that are specifically useful for drug addiction.

-Josh Gordon

Can being addicted to drugs and alcohol be genetic?

-fdavid, Illinois

hey fdavid, yes genetic factors do play a role in addiction to drugs and alcohol. It is estimated that about half the risk is genetic and half environmental (social support, access to drugs, stress, etc.)

-Maureen Boyle

What is the rehab process- and what components of it make one overcome their addiction/problem? How effective is rehabilitation, and how many people actually overcome their addiction?

-Nicholas S, New York
Thanks for your question. The amount of time it takes to go through rehab for addiction depends on many factors including the person, their genetic makeup, behavior, how serious the problem is, whether the rehab is in-patient or out-patient, and the addiction they are trying to overcome. Effectiveness also varies. However, rehab certainly can help a person deal with their addiction(s). Read more about the treatment process at
-Albert Avila

what's the difference of molly and ecstasy?

-janemiz, Rhode Island

Hey janemiz! Ecstasy and Molly are both names that people use to describe the chemical MDMA, a drug that causes changes in mood and perception. While some people think that Molly is a "pure" form of this chemical, Molly can contain additives or other dangerous drugs. To check out more facts on MDMA, visit:

-Emily Einstein

Do drugs and alcohol affect school work?

-psaleh, Illinois

Yes and it will depend on how much and how frequently you take them.

Nicotine will not affect your school work but it can make you addicted

Marijuana has long lasting effects in your brain that will impair your memory, attention, and interest

Alcohol can lead to risky beahviors that also can interfere with how you perform at school

-Nora Volkow

How accurate do you believe the network portrays addiction in television shows and movies

-EJS, Maryland

Hi EJS: There are many examples of accurate portrayal of addiction in film. I can think of "Flight" with Denzel Washington, "Trainspotting", "Requiem for a dream"... and I am sure there are many more. Addiction can have devastating consequences, and movies can be a powerful way to show that.

-Anto Bonci

what is the synergistic affect of taking alcohol and marijuana together?

-janemiz, Rhode Island

Hi janemiz,
Great question -- we still don't know how alcohol and marijuana work together in the brain (synergistic effects), except in the case of driving ability: Studies show that drivers who use both marijuana and alcohol are at an even greater risk for an accident than if they use either drug by itself.

-Eric Wargo

Can you explain the connection between marijuana and schizophrenia?

-etarshish, Illinois

Marijuana interferes with processing of sensations and thinking, which is why it can lead to a misrepresentaiton of reality that can result in paranoia and full blown psyshcoses where you cannot recognize what is real from what is not

-Nora Volkow

How does rehab help those who are addicted to drugs and alcohol?

-fdavid, Illinois

Dear fdavid,

Thanks for asking a great question. Rehab comes in many different forms.

There are medications to help with some addictions including nicotine/tobacco, alcohol, and opioids (e.g., heroin or prescription pain relievers). And there are also behavioral therapies 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. You can learn more about effective treatment programs here:

-Michelle Leff

What is the difference between depression and stress?

-kblair, Illinois

If you meen feeling stressed, that is a pretty natural response to whatever stressful things are going on in your life (school, parents, friends), and tends to happen while those difficult things are going on. Depression is a longer term illness where you might feel sad or unable to feel happy about things even if there aren't necessarily a ton of stressful things going on right then. Here's a bit more information on depression, and some of the symptoms:

-Susan Borja

Why does the body become so dependent on drugs dependent on drugs and alcohol?

-fdavid, Illinois
Alcohol is a drug that tricks the brain into making a person feel different for a little while. Some people like this feeling and choose to drink alcohol for that reason. If they keep drinking alcohol their body becomes dependent on the alcohol to feel normal. Over time, this develops into an addiction. That is, the person doesn't feel okay without the alcohol and they have a strong urge to drink. You can learn more about alcohol problems at Rethinking Drinking.
-Aaron White

What are some treatment for drug addiction?

-Abucal, Illinois

For drugs like heroin, alcohol, and tobacco there are medications.

For these and other drugs there are behavioral treatmenst that can help a person stop taking drugs

-Nora Volkow

If depression, suicide, and other mental disorders run in your family, does this mean that your chances for depression and suicide are higher? How can you prevent this?

-sbernstein, Illinois

This is a great question! Depression, suicide, and other mental illnesses do indeed "run in families," that is, if you have members of your family who have suffered from mental illness you do have higher chances of getting them yourself. We don't know a lot about factors that can help reduce this risk, though we think that things like getting enough sleep, staying physically active, and having an active social life may help. One important thing to do is to stay vigilant -- if you do start to feel depressed, getting treatment quickly can really make a difference.

--Joshua Gordon

-Josh Gordon

why does your environment effect your future to alcohol and drugs

-kharris, Illinois

Hi kharris,
Great question. Your environment, including your past (childhood) environment, includes things like your family life, your neighborhood, your school -- and all these things can make using or getting addicted to drugs harder or easier, depending. If your home is a stressful environment, for example, you may be more stressed yourself, and more likely to use drugs to escape stress. If a lot of people in your school use drugs, it can also make you more likely to.

-Eric Wargo

why does alcohol and drugs affect your baby when youre pregnant

-kharris, Illinois

This is a great question. We do know that alcohol, drugs, and even infections can affect the developing nervous system far more than they might in an already developed nervous system. This is why doctors advise women who are thinking about getting pregnant or are pregnant to be careful about what they ingest - this includes prescribed medications, too. For more information, check out this blog post:

-Michelle Leff

how do you know if someone is a crackhead and how do you help them

-stpehen curry, Illinois

It depends on the drug. Some drugs have clear signs. For example, your eyes' pupils become bigger (dilated) when you take LSD, but contract when you take an opioid (pin point pupils). But just because someone's pupils are dilated or contracted, doesn't mean they are on a drug -- other things can cause those effects, too. Drugs can also increase or decrease heart rate or breathing rate, but those effects can also happen without drugs. The only way to tell for sure is to test for the presence of the drug in bodily fluids like blood or urine.

If you know someone who uses illicit drugs of any type regularly to the point that it affects their health, relations with family & friends, and ability to do their school work, they may need help. More info is at: Good luck!

-Aria Crump

Dear Dr. Jack Stein, Thank you for supplying the pizza, and i wanted to know how you solve addiction

-Dorey, Illinois

Hi! Sorry can't send you a slice :)

NIDA is ALL about trying to solve the addiction problem. We are conducting research to answer the many complex problems related to why and how people develop problems with drugs and how to prevent and treat it. We've learned lots but have a ways to go. Keep tracking our progress on our website:

Dr. Jack

-Maureen Boyle

What are some of the genetic effects of people who used drugs and alcohole alot through your ancestry? -Chris

-GHS, Massachusetts

Great question! -- This is something we're busy studying. It's a new topic called "epigenetics" -- the way behavior (like drug taking) can actually affect people's children and grandchildren -- pretty amazing, huh! Although you can't change your actual genes, taking drugs may affect which genes are expressed (switched on or off, like a switch), and this can be passed on to your kids. Some animal research has shown that drug-taking can cause drug seeking in offspring.

-Eric Wargo

what is the general age for people to start smoking and what are good ways to avoid peer pressure

-Cchrisp, Illinois

Hi, Cchrisp, thanks for your question. According to the 2015 National Survey on Drug Use and Health, the average age people start smoking cigarettes is 18 years old. The average age among kids who start smoking before they turn 18 (underage) is 15 years old. NIDA has a Drug and Health Blog post about peer pressure here: that may be useful. It's also helpful to be equipped with facts to help you make decisions that are right for you, so here is some information about the health effects of drugs on NIDA’s teen site: When it comes down to it if you have friends who are pressuring you to do something you don't really want to, perhaps they aren't friends after all. Surround yourself with peers who will support you no matter what!

-Marsha Lopez

Why do women have a lower alcohol tolerance than men

-kenzie@gentryJR, Texas

It isn't the case that women have less tolerance, but women tend to weight less than men and have less water in their bodies compared to men of the same weight. As a result, if a woman and a man of the same body weight each have a drink, the woman will likely reach a higher blood alcohol level than the man.

-Aaron White

Now that medical marijuana is legal in the usa and you can grow it in area and sell it do you think that would spark up more drug proplomes or less because it allowed in the long run homing in on a certan part of marihuana history would laced marijuana be worse or better? -Chris

-GHS, Massachusetts

Its too early to tell, and we are doing active research on the effects of such changes. The experience so far and the monitoring data suggest that, aside from some potentially worrisome observations regarding vehicular accidents and emergency rooms, the sky isnt falling. As always, the future is particularly difficult to predict.

-Ruben Baler

whats the best way for a parent to cope with their child who has an addiction and wont listen??

-duroon n pom, New York

Hi duroon n pom

I hear you. This is unfortunately a common situation between the drug using child and their parents. It is best for the parents to talk to their pediatrician for help. Either the pediatrician will have someone in their office trained to talk to youth with substance use issues and finally help them stop using drugs; or they can refer them to a trained provider in the community.
Most of the treatments that work for substance abusers involve changing one's behavior through counseling and behavioral and family interventions.
Here's are a couple of sources of information about treatment:

The following might be a helpful resource for the parents

-Geetha Subramaniam