Marijuana use may speed psychosis
February 7th, 2011
05:56 PM ET

Marijuana use may speed psychosis

Using marijuana, or cannabis, may cause psychosis to develop sooner in patients already predisposed to developing it, and in other patients the drug may even cause psychosis, according to a new study published in the Archives of General Psychiatry.

"This finding is an important breakthrough in our understanding of the relationship between cannabis use and psychosis," according to the study. "It raises the question of whether those substance users would still have gone on to develop psychosis a few years later."

Patients with psychosis tend to lose touch with reality and are prone to hallucinations and delusions about what is happening around them.  Psychosis is frequently reported among patients with diagnosed mental illness such as schizophrenia and bipolar disorder.

What is schizophrenia?

According to the study led by Australian researchers, in which data from 83 studies involving more than 20,000 patients were analyzed, marijuana  users experienced psychosis about three years younger than non-users.  Users of other substances (besides pot) experienced symptoms of psychosis two years sooner. Alcohol use  had no influence on development of psychosis, according to the study.

"Reducing the use of cannabis could be one of the few ways of altering the outcome of the illness because earlier onset of schizophrenia is associated with a worse prognosis," according to the study.  "An extra two or three years of psychosis-free functioning could allow many patients to achieve the important developmental milestones of late adolescence and early adulthood that could lower the long-term disability arising from psychotic disorders."

But experts say the complexity of interaction between genes and environment, and the possibility that cannabis is, in fact, a way to self-medicate when psychotic symptoms arise are not accounted for in this study.

The marijuana-schizophrenia link

"It is distinctly possible, in fact likely, that folks who experience initial symptoms turn to cannabis in an effort to control them, then end up having a psychotic break of some sort earlier simply because they had their first symptoms earlier," said Mitch Earleywine, an associate professor of psychology at the State University of New York at Albany, who is also a marijuana policy expert. "This predicament makes it look as if cannabis preceded the psychotic symptoms when, in fact...folks with worse symptoms who are more likely to have an early break might simply be more likely to turn to cannabis."

Theories about an association between marijuana use and schizophrenia include several –sometimes interrelated - scenarios: The possibility that cannabis causes schizophrenia; that cannabis may cause people vulnerable to schizophrenia to develop symptoms; that cannabis may make schizophrenia symptoms worse; or that people with schizophrenia are more likely to use cannabis, according to the study.

Study authors suggest that this study, "lends weight to the view that cannabis use precipitates schizophrenia and other psychotic disorders," perhaps because of some confluence of genetic and environmental factors, or because using cannabis early in life may disrupt brain development.

"[This study] found that cannabis is associated with early onset of psychosis and that is most likely true but it doesn't answer the question of which way it goes," said Dr. Charles L. Raison, associate professor in the department of psychiatry at Emory University, and CNNHealth's mental health expert doctor. "Does smoking cannabis early in life make you vulnerable to getting early psychosis or is the first manifestation of psychosis to do drugs and alcohol, or is it both?"

Do you have diagnosed schizophrenia? How well are you managing it?

Raison added that other studies suggesting a causal relationship between marijuana  use and psychosis disagree with this one.

Whatever the relationship between cannabis and psychosis, experts can agree that early use of cannabis is problematic.

"No one wants to see young people get heavily involved with any psychoactive substances," said Earleywine.

soundoff (1,357 Responses)
  1. Kevin

    "It raises the question of whether those substance users would still have gone on to develop psychosis a few years later."

    Pardon me, but shouldn't you be working on ANSWERING the question? Nothing in the study indicates any causal link between cannabis and schizophrenia. This is every bit as flawed as the "vaccines-cause-autism" study. Correlation is not causality.

    And how, exactly, did this study execute the arrangement of its control group?

    February 8, 2011 at 08:44 | Report abuse | Reply
  2. DolarPeso

    Moral of the story: Crazy people shouldn't smoke pot.

    February 8, 2011 at 08:46 | Report abuse | Reply
  3. isadore

    The article says alcohol does not cause psychosis. My mother was a raging alcoholic. Sometimes when she was really drunk, she would try to drown me in the bathtub as a child. Luckily she was wasted enough I managed to escape (couple close calls). Anyhow, later on I was told she suffers alcohol psychosis!
    I have extreme PTSD now (um...u think?) and I smoke weed to help. I tried the drugs prescribed to me by docs and psychiatric hospitals. They are far more intense and I could not function on them.

    February 8, 2011 at 08:49 | Report abuse | Reply
  4. Redman71

    Reefer Madness is alive and well 75 years later. Complete B.S. cannabis is one of the most natural, non-toxic substances on the planet. You doubters need to study up on cannabinoids, and the relation between the plant and human body. Free the weed!

    Do you honestly think that God made an "illegal plant"?

    Genesis 1:29-"And God said, Behold, I have given you every herb bearing seed, which [is] upon the face of all the earth, and every tree, in the which [is] the fruit of a tree yielding seed."

    February 8, 2011 at 08:50 | Report abuse | Reply
  5. Me Too

    I watched my schizo sister in law talk to a TV one night when she was high. One of those criminal shows where a lawyer was asking a defendant questions, and my sister in law was answering! I went upstairs and told my wife, we both thought we were gonna die that night. Pot definitely made her worse. I'm not just saying she was nuts, she was in and out of nut houses since she was 12, even attacked her mother with a knife. Once she took a 100 foot garden hose and tried to hook it to her exaust. 100 feet, LMAO. Good thing she was stupid, too.

    February 8, 2011 at 08:52 | Report abuse | Reply
  6. Redman71

    I think that chick had a few more problems than smoking a little weed dude....

    February 8, 2011 at 08:54 | Report abuse | Reply
  7. Myself and I

    Has the exact opposite effect, in my lengthy experience. But, everyone's built differently. And people have to recognize, that, instead of one group trying to get another group to live the way they think life is to be lived. To the point of persecuting those people through drug laws, etc. It's time to stop the madness. To paraphrase the governor of California – "nobody cares if you smoke a joint anymore". Except for a few nutjobs.

    February 8, 2011 at 08:55 | Report abuse | Reply
  8. DALE

    This is stupid, I've never heard of anything as...wait, hold on, there's somebody at the door...quiet.........okay they're gone...what was I saying?

    February 8, 2011 at 08:58 | Report abuse | Reply
  9. Myself and I

    "Whatever the relationship between cannabis and psychosis, experts can agree that early use of cannabis is problematic."

    What experts? This is the same scare tactics that are always dragged out, whenever sanity threatens to enter the marijuana debate.

    The nutjobs aren't the kids smoking dope – the nutjobs are the ones trying to raise the spectre of reefer madness yet again.

    February 8, 2011 at 09:00 | Report abuse | Reply
    • DolarPeso

      Ok, well let me be proof that it isn't problematic for those who start at an early age. I started smoking pot at 13 and quit at 33. I'm ok, but I do agree kids shouldn't be doing anything that gets you high or drunk.

      February 8, 2011 at 09:26 | Report abuse |
  10. GoOhio

    Let me just say that I am not for or against pot. I have found that It's not for me. It may help in certain ways but I do think that it has its cons as well... I first got high at the age of 13. It messed me up pretty bad for a couple days. This story really makes sense. No, I'm not a crazy. I do have bi-polar behavior as well as schitzy. I developed this after the first time I got high. I became very paranoid. Would I have developed this disorder without smoking? I'm not sure. But I feel 100% positive that pot triggered it. I vouched to never touch it again.... A couple years later I became a pothead (last year of HS). It seemed to help things while I was high. Once I quit, things were even worse. Now I'm no expert but in my case, I have to agree with the scientist on this one. I really think they are on to something.... Hopefully they develop a new weed I can smoke that doesn't cause parnonia, schitz, or bi-polar disorders lol. I liked smoking but I hated feeling paranoid! I'm being funny, but my testimony is the truth. There is no history of psychosis in my family for what it's worth.

    February 8, 2011 at 09:05 | Report abuse | Reply
  11. Van Gogh

    This article is pure BS. Pure BS. For every study that says these things there are other studies that prove the opposite.

    Marijuana is a PLANT, plain and simple. A PLANT!

    February 8, 2011 at 09:08 | Report abuse | Reply
  12. dj30harw

    Maybe the "scientist" should start studying real issues with drug use... maybe examine PHARMACEUTICALS, the real drug threat in our country.

    February 8, 2011 at 09:12 | Report abuse | Reply
  13. tommy

    And 90 years ago, Anslinger made movies like Reefer Madness..... the government's propoganda on marijuana is disgusting, and listen folks, when they lie about something as simple as a god given plant, when the heck else are they lying about.

    As consumers of News... we should demand the honest reporting of fact, not conjecture, not someone's unproven analysis..... the openng paragraph of this article, and I use that term very loosely builds it's case around the word "may" twice, it may to this or it may do that, or it may cause this....... total baloney..... he scientists, monkey's "may" fly out of my butt any second..... or the world "may" end tomorrow... this is more like a commercial of someones opinion than actual science.

    February 8, 2011 at 09:15 | Report abuse | Reply
  14. Relative

    I have a relative who was into drugs mainly marijuana (in the 1970s — 33 years ago) who developed schizophrenia (at 19 years-old) it is a heart wrenching disease. You grieve for that person you grieve because it never gets better. It is tragic to watch and experience especially when they are violent. I tell my children they can never do drugs as we have this in our family and it is not worth the risk.

    February 8, 2011 at 09:15 | Report abuse | Reply
    • dj30harw

      So what other drugs was he into? I love how you fail to mention them.....

      February 8, 2011 at 09:20 | Report abuse |
  15. Garrett

    Alcohol also speeds up psychosis...ever seen a drunk in a bar...We need to write about the BIGGEST health threat to this country.

    February 8, 2011 at 09:17 | Report abuse | Reply
  16. tommy

    haahaahaa..... I figured out their ruse.... this is a peer study, not patients were actually assessed, they merely accessed a bunch of databases and tried to masterbate statistics together for a propogranda orgasim..... and the news reported it as such. Again... no single person was actually evaluated, this is merely meta data analysis... which in itself biased based upon the desired outcome of the analyst. Which is why you can give the same set of budget numbers to a republican and a democrat and they will give a totally different result with different meanings.... What a joke... hey scientists.... when you really start conducting scientific experiments with marijuana let us know.... otherwise, I'll go by the 5000 years of sucessful human use as a holy sacriment from God.

    February 8, 2011 at 09:21 | Report abuse | Reply
  17. Thatsloadofcrap

    Thats not the truth its fiber and omega 3 oil. The same omega 3 oil in fish oil. What causes pyschosis is a cat parasite from handling cat poop.
    Search ResultsToxoplasmosis Parasite May Trigger Schizophrenia And Bipolar DisordersMar 11, 2009 ... Toxoplasmosis is a parasitic disease, primarily carried by cats. ... to bipolar disorder or schizophrenia in youth, according to a new . ...
    http://www.sciencedaily.com/releases/2009/03/090311085151.htm – Cached – Similar

    February 8, 2011 at 09:24 | Report abuse | Reply
  18. Hawkeye

    Environment and genes. HHMMM, seems like we've got a ways to go before truly figuring this out. I for one see the environment as the single most destructive source of the Human Body. Stress, HELLO, and all the pollution in air. Could it be people in bigger city with more pollution have a higher chance of getting Phychosis? I'm sorry but Marijuana effects everyone differently, just like different Alcohols effect people differently. It really all comes down to if you have evolved enough to assimilate the chemicals in the air.

    February 8, 2011 at 09:24 | Report abuse | Reply
  19. The Jackdaw

    Right. And not wearing shoes might make me a messiah.

    February 8, 2011 at 09:29 | Report abuse | Reply
  20. Thatsloadofcrap

    No one wants to believe that parasites can cause mental illness even when you kiss your dog or cat after its been grooming its self licking its rear end the worms that live in uncooked meat.leave meat sit out to long and what is a result ? maggots or parasites, theres hook worms, tape worms,pin womrs,ring worm and thousands of other parasitic creators that cause a variety of illness's uncooked meat and fish.A parasite can lay thousands of eggs so it can be hard to combat and even the eggs can be mistaken for a virus. Bovine Parasites and lunk parasites

    February 8, 2011 at 09:30 | Report abuse | Reply
  21. reallynow

    What a sham this study is. Enough said.

    February 8, 2011 at 09:30 | Report abuse | Reply
  22. Social Worky

    Um ……. Would not the increase in young people using marijuana result in an increase in the average percentage of the population suffering from schizophrenia? One would think, but that number remains steady …….. yes, these people were intentionally looking for an ‘ice-cream' correlation.

    February 8, 2011 at 09:33 | Report abuse | Reply
  23. elo

    I am a therapist and I work on a psych ward. You dont need a study for this...its old news. A good portion of people who come on the unit have "substance induced psychosis". Wake up MJ and drug users. Youre in denial.

    February 8, 2011 at 09:34 | Report abuse | Reply
  24. eric

    "It is no measure of health to be well adjusted to a profoundly sick society"


    "Insanity in the individual is rare. But in groups, parties, nations, and epochs it is the rule"

    Friedrich Nietzsche

    February 8, 2011 at 09:35 | Report abuse | Reply
  25. B. Sol

    That's fine. Why take chances, right? But this "study" shows a correlation, not a cause. Schizophrenia has a very specific onset. It's extremely rare for it to appear in individuals past their teens and 20s. If marijuana shared a causal relationship with schizophrenia, you would see onset in marijuana users at any age. That's not the case.

    There also happens to be a positive correlation between alcohol abuse and schizophrenia. But most people reading that statement tend to take the view that this is a result of self-medication. After all, it's a well-known fact that many alcoholics become so to "escape their demons". It makes sense, right? It also clearly demonstrates how personal bias makes correlational studies completely useless.

    If it's alcohol, then schizophrenia leads people to drink.

    If it's marijuana, then marijuana causes people to develop schizeophrenia...but only if they already have it.

    Cmon, people. Don't fall for this pseudo-scientific garbage.

    February 8, 2011 at 09:40 | Report abuse | Reply
  26. lefty avenger

    Marijuana is a natural herb. Many people smoke pot and are productive members of society. Big Pharma is the biggest drug pusher in america. Peddling opiated pain killers that addict and ruin people's lives. Peddling anti-depressants that cause people to commit suicide. The Big Drug companies demonize natural cannabis because they want you to buy their much more dangerous dope. Drug War? for what, so these corporate giants to be the biggest global dealers?

    February 8, 2011 at 09:41 | Report abuse | Reply
  27. avid

    I am currently conducting a study on how the internet causes dimentia....my case study is this article!!!

    February 8, 2011 at 09:41 | Report abuse | Reply
  28. Chris

    Funny how it states alcohol doesn't create psychosis. Really, how many crimes are committed each day due to alcohol?

    February 8, 2011 at 09:42 | Report abuse | Reply
  29. Thatsloadofcrap

    No one wants to believe that parasites can cause mental illness even when you kiss your dog or cat after its been grooming its self licking its rear end the worms that live in uncooked meat.leave meat sit out to long and what is a result ? maggots or parasites, theres hook worms, tape worms,pin womrs,ring worm and thousands of other parasitic creators that cause a variety of illness's uncooked meat and fish.A parasite can lay thousands of eggs so it can be hard to combat and even the eggs can be mistaken for a virus. Bovine Parasites and lung parasites. Do the research on cat parasites and bi polar cat parsites and schizophrenia. Read revleations 8:11 wormwood which is probably refering to parsites. 3 herbs work together to kill these parasites wormwood blacknutt hulls and freshly ground cloves.

    February 8, 2011 at 09:45 | Report abuse | Reply
  30. Torrent

    I demand you remove this B.S report- "Marijuana use MAY speed psychosis"
    guess what i MAY break my foot in ur ass.
    Hey Stephanie Smith – How much did they pay you to put this crap up on cnn.

    February 8, 2011 at 09:45 | Report abuse | Reply
  31. Jeff

    Get a life...why dont we conduct a study to find out how how many pills, and how much alcohol is consumed by the morons reporting this story. Better yet, the same study should be conducted on the so called experts who are trying to make marijuana sound like herion. Youre not going to eradicate it from this earth...move on to a fight you can win.

    February 8, 2011 at 09:48 | Report abuse | Reply
  32. drug commercial plague

    What about the barrage of commercials for various experimental psychotropic drugs that air non stop on every channel on tv.?

    Ever read the side effects to some of these? Ever notice antidepressant pills tend to cause suicidal tendencies?

    February 8, 2011 at 09:52 | Report abuse | Reply
  33. sicktruth

    I concur. Sounds like a study paid for by the pharma corps....don't smoke or ingest something naturally grown, instead use our magical pills for all your ailments. Sorry about the side effects that cause leaking anuses, blurred vision, and the urge to kill everything....it really only happens to a "few" people.

    I agree.

    February 8, 2011 at 09:54 | Report abuse | Reply
  34. mrrusss

    What is the crap all the time about studies that indicate something "may" do something else. Isn't that the point of the scientific method, and having a study; to find out something conclusively. I thought a scientific study was supposed to START with "something MAY happen". I have a study. Studies I've performed indicate that women who do whatever their man tells them MAY experience loss of cellulite, disappearance of fine lines and wrinkles, and increased cup size.

    February 8, 2011 at 09:55 | Report abuse | Reply
  35. Jimbo

    BS, this is junk science plain and simple. Maybe this and maybe that, but we don't really know. Then why write an article, oh that's right it's propoganda used to convince someone of something.

    February 8, 2011 at 09:55 | Report abuse | Reply
  36. Alex

    I want to be a scientist 🙂

    February 8, 2011 at 09:56 | Report abuse | Reply
  37. Jim in Florida

    Guess dweebs like Michael Moore and Oliver Stone have smoked a whole mountainside of good hooch lol

    February 8, 2011 at 09:57 | Report abuse | Reply
  38. Dood

    I have no doubt in my mind that marijuana is linked to psychosis. It's happened to me twice after a couple of periods of daily smoking for at least a year. Regardless, Marijuana should still be legal. MOST people have no negative side effects, and the fact that it is illegal is causing way more harm than it would if it was legal.

    February 8, 2011 at 09:58 | Report abuse | Reply
    • mrrusss

      You got high every day? What a testimony for the safety of marijuana. Try getting drunk every day for a year. You'd be dead.

      February 8, 2011 at 10:02 | Report abuse |
    • Dood

      That's the beautiful thing about tolerance! You can drink everyday for a year! But it will destroy every aspect of who you are, unless your personal preference is to be a giant dong for the rest of your life. I really enjoyed smoking, and if it didn't make me crazy, I'd still be smoking. It's pleasant, makes eating more enjoyable, makes thinking more interesting – with more depth, and it's a great social activity. All of the legal substances are horrible, and massively physically and mentally damaging. But, psychosis really sucks too. Still, it's pretty ass backwards considering you can go to the doctor and get a prescription of benzos that could actually kill you from the withdrawals, or go to the store and stock up on alcohol that is easy to overdose on, and can kill you from the withdrawals.

      February 8, 2011 at 10:13 | Report abuse |
    • Jorge

      Dood, some giant dongs who drink/drank every day have about 100 times more brains(Thomas Jefferson, Winston Churchill, F. Scott Fitzgerald) than a lot of sober people I know. You be a teetotaller, I'll continue to take my daily nightcap and continue to proofread and edit for my dry, dyslexic Baptist boss who can't redact or spell worth a rat's rump.

      February 8, 2011 at 10:41 | Report abuse |
  39. nepawoods

    This is old non-news, reported many times in past: Correlation found, but no evidence of causation found. People experiencing distress associated with psychological or psychiatric issues, including undiagnosed early stage ones, will seek to alleviate their symptoms, often by "self medicating". They can do a lot worse than turning to marijuana. There is no evidence (the researchers acknowledge this) that marijuana makes matters worse. Their particular study didn't find evidence it doesn't, so not finding evidence it doesn't, they can say MAYBE it does.

    February 8, 2011 at 09:58 | Report abuse | Reply
  40. mrrusss

    Studies indicate that the incredible amount of alcohol use, (you know, that sh***y drug that destroys your brain and body, is the most addictive drug on the planet, and worst of all, is a sh***y buzz), contributes to the similarities between society today and the movie Idiocracy.

    February 8, 2011 at 09:59 | Report abuse | Reply
  41. Not All Docs Play Golf

    So...Reefer Madness was all true! OMG! That must mean that they were also right when they told us playing with yourself would make you go blind! OMG!

    February 8, 2011 at 09:59 | Report abuse | Reply
  42. lolwut

    ITT: trolls trolling trolls trolling trolls

    February 8, 2011 at 10:00 | Report abuse | Reply
  43. demilioso

    Personally, I don't care if marijuana is legalized. What bothers me is that, as evidenced in these comments, people who smoke marijuana aren't content to just smoke it, but they feel the need to try and tell everybody that the drug is a positive good. That's a crock of BS. You like to get high? Fine. But stop the non-sense. I can handle someone who admits they like/do bad things. I cannot handle someone who tries to tell everyone that his/her bad habits are actually a good thing.

    February 8, 2011 at 10:02 | Report abuse | Reply
  44. NOTtrueforme

    I completely disagree with this article. I realize things work differently for different people though. I was diagnosed with bipolar disorder along with manic depression and borderline personality disorder. They had me on lithium, and SEVERAL other drugs that made me a zombie. I eventually slowly stopped taking them and began smoking pot instead. Since I've done that, I've had a much better outlook on life, and just a more enjoyable one. I've not lost my mind once, nor have I been suicidal or just went crazy on someone. Pot saved my life..and my mind. I know that there are downsides to everything you can take. You can become addicted, you can have different side effects from smoking pot, but it works for some people. I don't know why we can't just let it work for who it works for and everyone else doesn't have to take it.

    February 8, 2011 at 10:02 | Report abuse | Reply
  45. And

    Good thing I just stick acid drops on the inside of my eyelids, snort pcp, and inject a daily IV of heroin. But no pot for me so I'm good!!

    February 8, 2011 at 10:05 | Report abuse | Reply
  46. T.Brown

    The weed I smoked back in the day(70's-80's) was powerful enough..."Acapulco Gold" to be exact.This weed would, i'd swear make you see FANTASTIC cloud formations,your minds eye and hearing was so expanded that you could visualize and hear...and I'am trying to explain it truthfully..a.. Prehistoric Jungle!!,predator and prey at the same time you were always on the verge of panic/bliss..and that was just one episode I remember.My point?.The weed produced today has far more THC in it than what I smoked.Some of the people I hung out with are TO THIS DAY baked out of their minds and all they talk about is Back In The Day...SO I kind of believe the study based on the people I know...now did they do acid? I say yeah but very,very rarely...but we did have some damn good laughs and ate peanut butter and jelly with balonie and cheese sandwiches....yeaah.

    February 8, 2011 at 10:07 | Report abuse | Reply
    • Kermit Roosevelt

      Can I buy some pot from you?

      February 8, 2011 at 10:24 | Report abuse |
  47. Dick Hertz

    If my Aunt had balls she'd be my Uncle. I've been smoking for 42 yrs (every day) and I'm still waiting to see all these terrible side effects.

    February 8, 2011 at 10:11 | Report abuse | Reply
    • Sandyj71

      Right on Dick!! I'm right behind you, but with only 25 years under my belt!!! Still waiting for all these "bad things" to happen to me.....

      February 8, 2011 at 11:18 | Report abuse |
    • harlem hutch

      Tell it like it is Dick! I'm a 40 year veteran. Nectar of the Gods!

      February 8, 2011 at 12:00 | Report abuse |
  48. Tonic

    This article/"study" is ridiculous. CRAZY people are sparked into craziness by almost anything – something is going to trigger it.

    February 8, 2011 at 10:13 | Report abuse | Reply
  49. jiff

    you want a marijuana "use" expert talk to emily

    February 8, 2011 at 10:24 | Report abuse | Reply
  50. Jorge

    Oh brother, I fear for the future of the world if left in the hands of modern day "professionals". To a psychotic, pretty much anything that gives a buzz or rubs him/her the wrong way will accelerate his/her condition. Prisons and cemetarys are full of loopy people who had a couple of drinks and got ten feet tall and bulletproof. It wasn't the booze, it was the voice in their heads that got louder...

    February 8, 2011 at 10:27 | Report abuse | Reply
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