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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can u get high off the smell of marijuana?

-chief_tru706, Maryland

hhi chief
no, you can't. but the smell could trigger cravings if you are a regular user.

-Ruben Baler


-AndreG, Texas


-Joni Rutter

can u overdose on alchol

-chief_tru706, Maryland

Definitely.  Alcohol poisoning occurs from a single episode of drinking way too much and you can potentially die from alcohol poisoning. Alcohol builds up in your bloodstream and can slow down important body processes like breathing and the gag reflex, which prevents you from choking. Even if you have stopped drinking or pass out, alcohol in the stomach and intestine can continue to enter your blood stream and circulate throughout your body.
Critical signs of alcohol poisoning include:

  • Mental confusion
  • Stupor
  • Coma
  • Vomiting
  • Seizures
  • Slow or irregular breathing
  • Hypothermia, or low temperature
  • Bluish skin color
  • Paleness

If you think someone you know may be experiencing alcohol poisoning, make sure to get help immediately. You can call 911. You can learn more about alcohol poisoning and overdoses at:

-Aaron White

can ur baby be effected by smoking

-seahawks boss 1, Georgia

Hi! Very important question. Tobacco is NOT safe to use in pregancy because it affects the developing baby.  You can read about the effects here: the good news is that the sooner a pregnant woman stops smoking, the better the outcome for her baby. It's also important not to smoke around the baby after birth because he or she can have health problems from secondhand smoke. 

-Cora Lee Wetherington

Can usage of an illegal substance while someone is pregnant, cause a miscarriage?

-agifford, New Hampshire

Yes, it is possible for drugs to cause a miscarriage.

-Gaya Dowling

can using steroids every once in a while be harmful ?

-ChailynF, Texas

Your own body produces all the steroids it needs...and it needs them to regulate your growth, and are critical for reproductive function. People who use large quantities of anabolic steroids (based on testosterone) risk heart disease, liver damage (even in young people), and may not reach their full height.  It also can cause aggression and male-pattern baldness (who needs that?), and if you are a female who is using anabolic steroids, your voice may deepen permanently, grow facial hair, and develop male-pattern baldness. The trick is that steroids must be present for a long time to see any effects, so occasional use is not likely to provide any good or bad effect. Other steroids like estrogen, progesterone, cortisol and cholesterol do not have the same effects as anabolic steroids. See for more info on steroids.

-Nancy Pilotte

Can weed cause cancer

-bruh79805, Michigan

Not sure yet about lung cancer.  It is also linked to an aggressive form of testicular cancer that affects young males.

-Nora Volkow

Can weed cause cancer?

-Tundraj, Texas

Hi Tundraj! Because a lot of people who smoke marijuana also smoke cigarettes, it's difficult to tell what increased risk of cancer comes from cigarette smoking, and how much of that risk is due to smoking marijuana. More research is needed in this area, but marijuana is addictive. 1 in 6 teens who use marijuana will get addicted to it, and 25-50% of those who use every day are addicted.  You can find out more about marijuana and addiction here:

-Joseph Frascella

can weed lead to vomiting?

-RaoK, Texas

yes--in fact people have been showing up in emergency rooms with what's called hyperemesis -- where they can't stop vomiting.   

-Susan Weiss

can weed make people go crazy

-brecks, Texas

Marijuana use has been associated with a number of mental conditions, including schizophrenia, psychosis, depression, anxiety, and suicidal thoughts or attempts. However it is not yet clear whether marijuana use directly causes or exacerbates these conditions. Currently, the strongest evidence is for the link between marijuana and psychosis.  Marijuana intoxication can, at high doses, produce a temporary psychosis, and it may play a role in the development of schizophrenia in vulnerable individuals especially those with increased genetic risk. 

-Maureen Boyle

Are there any professional purposes for marijuana?

-Somebody, Maryland

Good question, Somebody.  At the moment, there are a few medicinal uses for certain components of the marijuana plant.  Marinol and Dranabinol are drugs that act like certain chemicals from the marijuana plant.  There are other chemicals from the marijuana plant that are under investigation for other medicinal uses, but we all want to be certain that they are safe and effective! Here's some more info:

-Joni Rutter

Are there any really dangerous drugs that a lot of people don't know about, but still kills a lot of people?

-Dale Cooper, Maryland

Hi, Dale, that's a good but challenging question! All drugs affect the brain but in differently, and the effects of a drug can be so different for different people that what's harmless for one could be extremely dangerous for another. Having said that, some drugs, like meth, heroin and many synthetics (which come laced with toxic chemicals) are notoriously harmful to your health. Bottom line- all drugs are potentially dangerous especially to a developing brain.

PS: our brains are developing until our mid 20s! So choose to live a healthy, drug-free life for your own health's sake. 

-Marsha Lopez

Are there any statistics or studies which show that marijuana is harmful when used casually?

-lackofagoodname, Maryland

There are a few recent brain imaging studies that suggested occasional use can alter the volumes of different brain structures.  But these data are still preliminary  (very small numbers of subjects)  Most of the research showing effects are in  people who use the drug regularly and started as teens.  This is a very important question that we hope to study in the near future.

-Susan Weiss

Are there any studies or research that point to possible long-term negative side effects of using ADD/ADHD meds in children (i.e. prescribed)?

-BarrieUSDean, Maryland

hi--this is a great question!  The research is somewhat mixed, but in general, we know that effective treatment for ADHD can help, not just with symptoms, but also with daily functioning, including social functioning with friends and families, and functioning at school.  So if a kid gets good treatment, they are more likely to get along with family and friends and do better at school, and later, more likely to succeed with college or jobs.  So for many people, the long-term benefit outweighs the negative side effects.  When people are treated with medication for ADHD, it's important to work closely with the doctor to discuss the balance of positives and side effects. Sometimes when there are side effects, adjusting medications or changing medications can help. 

-Joel Sherrill

Are there certain drugs that enhance sexual performance or pleasure? (Other than viagra and female-viagra)

-Lanthirey, Maryland

Hi Lanthirey,
A type of inhalants called amyl nitrites can enhance sexual pleasure--they were popular in the sexually liberated 1970s. Alcohol often increases sex drive but decreases performance. Stimulant drugs sometimes increase sex drive, but some like meth often have the opposite effect. 

-Eric Wargo

Are there different kinds of marijuana

-LJordan, New Hampshire

Hi LJordan,
Yes, there are two subspecies of Cannabis sativa: Cannabis sativa sativa and Cannabis sativa indica. Most street marijuana is Cannabis sativa sativa. Within that, there are hundreds of different strains or varieties, bred to have subtly different effects because of different amounts of the active chemicals (THC, CBD, etc.).

-Eric Wargo

are there effective treatments for drug addiction?

-jordanf, Ohio

hi Jordan  thanks for reaching out

Great question! There are some very effective treatments for drug abuse problems. Some of these are medications to reduce craving for drugs or manage the uncomfortable symptoms of withdrawal fom an addicitive drug. Other  treatments are psychosocial: They involve people interacting with people who help one to stop using drugs. Some proven effective psychosocial tretaments include cognitive-behaviroal therapies, motivational enahncement therapies, contingency management therapies, and mindfulness based therapies.

These all work really well for a lot of people. Unfortunaltely, we dont have enough treamtment opportunities for all the people who need them.

To find out more about treatments, you can visit:

-Harold Perl

Are there things besides drugs people can get addicted to? I've heard of people being addicted to porn/sex, and there's shows where people are addicted to eating strange things. Are those real addictions? Do they affect people the same way as drug addictions do?

-Annika, Maryland

hi annika
absolutely, there are several behaviors, besides psychoactive drug ingestion, that can produce short-term reward and that may engender persistent behaviors despite knowledge of adverse consequences, i.e., diminished control over the behavior. These addiction involve a very similar brain circuitry. we are only beginning to study such behavioral addiction applying some of the lessons we learned from drug addiction.


-Ruben Baler

Are there things like e-hookahs and if so why are they not more common?

-$$$fordayzzz, Minnesota

E-hookah is just a name for electronic cigarette...those are quite common!

-Kevin Walton

Are vape pens bad for you?

-DHSmember#2, Maryland

Hi DHSmember#2,
Great question, and unfortunately the answer is we still don't know, because they are so new. Even though they don't produce tar like cigarettes, they contain other unknown chemicals, and possibly toxic metals. And nicotine itself, which is in most of the fluids, is a highly addictive drug. One of its possible effects is making it easier to become addicted to other substances. It also might lead some people to use regular cigarettes, which are very bad for you.

-Eric Wargo

Are vape pens bad for you? If so how?

-Kearsarge, New Hampshire

The short answer to your question is--if you are not a current smoker, you are better off to never start. There is very little regulation of this industry so they are not required to disclose all of the chemicals that are in these products. We do know that nicotine is addictive and if you use it for nicotine, it can certainly increase risk of addiction. Also, vapor from some e-cigarette products has been found to contain known carcinogens and toxic chemicals including formaldehyde. Until more studies are conducted, there is no way of knowing what the health consequences of repeated exposure to these chemicals may be.

-Roger Little

Are vaporizer pens dangerous?

-kearsarge, New Hampshire

Hi Kearsarge!  Thanks for your question!  'Vape pens', or e-cigarettes, don't produce smoke (like  with traditional cigarettes), but they do contain nicotine, which is addictive.  While many people think they are safe and a safe alternative to smoking traditional cigarettes, we don't currently know.  Luckily, scientists are currently doing research on e-cigarettes to figure out if and how they pose a danger to health.  Some things that we do know about e-cigs is that nicotine can effect the developing brain (and not necessarily in a good way).  It may be best to avoid use of these products until scientists can figure out what is in them, how they really work, any bad by-products they might produce and how they may impact your health!  

-Albert Avila

are vaporizers illegal? And do they make the weed less harmful?

-MarginalTrain, Minnesota

Hi MarginalTrain,
Vaporizers are legal. The only way they might make marijuana less harmful is by not producing as many chemicals that harm the lungs, but the main harms of marijuana are from the THC, which you get from vaping just as much as from smoking or eating.
Good question.

-Eric Wargo

Are whipped cream bottles classified as inhalants?

-becky, Florida

Becky,  You are correct.  In addition to being a yummy topping for ice cream sundays, whipped cream bottles are classified as inhalants.  For more information about inhalants and other drugs see:

-Redonna Chandler

Are you happy about how many questions are being asked today?

-eechase17, Minnesota

Yes, we're thrilled to be getting so many questions! Hope you're having fun and learning a lot!

-Maureen Boyle

Are you seeing a nationwide increase in heroin use? If so is this related to any particular age group?

-jmetcalf, Iowa

Hi, jmetcalf, although heroin use has increased since the early 2000s, despite recent media attention heroin we are not seeing a nationwide increase in use.  According to the National Survey on Drug Use and Health, about one tenth of a percent (0.1%) ages 12 or older were current heroin users in 2013 which is similar to those in 2008 to 2012. 

-Marsha Lopez

Around what age do kids start using cocaine?

-p.g.goalie, Maryland

Thanks for writing p.g.goalie!  According to a national survey, the mean age of initiation among teens who started using drugs prior to the age of 18 was about 16 years old. You can find more information at

-Mary Kautz

At what age do people start drinking illegally?

-heyncms, Maryland

Well, drinking under the age of 21 is illegal in the US. On average, the typical person in the US has their first drink at age 17.

-Aaron White

at what age do people usley start smoking

-cassidyb, Texas

Hi, cassidyb, I'll give you a couple of numbers to answer this one.  According to the National Survey on Drug Use and Health, among kids who initiated before they were 18 years old, the average age of starting to use illicit drugs was around 15 years old.  Among those who initiated between ages 12 and older, the average age was 20 years old.

-Marsha Lopez

at what age is the most common age for someone to start drugs?

-MeganS, Texas

Hi, MeganS, According to the National Survey on Drug Use and Health, among kids who initiated before they were 18 years old, the average age of starting to use illicit drugs was around 15 years old.  Among those who initiated between ages 12 and older, the average age was 20 years old.

-Marsha Lopez