New research links cannabis use and psychotic experiences

Aug 19, 2010
cannabis

Cannabis use among students can lead to psychotic experiences, according to new research led by the University of Bath.

Using has been related to psychotic experiences in the general population but few studies have examined this relationship in undergraduate students despite high levels of cannabis use in this group.

Thomas Richardson from the Mental Health Research & Development Unit, along with colleagues in Dublin, asked 334 undergraduate students in the UK, Ireland, Canada, USA, Australia and New Zealand to complete a questionnaire about their use of cannabis as well as a measure of psychotic symptoms.

The researchers found that those currently using cannabis were more likely to have had hallucinations such as hearing voices that other people cannot hear.

Those who used the drug more frequently were at a greater risk still of experiencing such hallucinations, and heavy use also increased the risk of having delusions such as believing that someone was reading their mind.

Thomas said: “The study found that those currently using cannabis had higher levels of hallucinatory experiences that those who were not using cannabis. More frequent use was related to an increased likelihood of hallucinations, and heavy use also increased the risk of experiencing delusions. This suggests that students who move from occasional, perhaps recreational cannabis use to more regular use are more likely to have psychotic experiences.

“I must stress the limitations of this research, but nonetheless these findings are important as undergraduate students as a population have very high levels of cannabis use. This research suggests that those who use cannabis are more likely to have psychotic experiences, which in the long run may increase the risk of developing a serious mental health problem. These results are therefore important for health professionals who work with students.”

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tida
4 / 5 (4) Aug 19, 2010
take into account that everyone in the world's perception is subjective. People claim everyday that god speaks to them and many are well respected members of society to say that cannabis makes people crazy is nonsense since i doubt most people no what crazy is i mean you could get chopped up by your next door nieghbor and never know he was a complete psycho
pauljpease
4.5 / 5 (11) Aug 19, 2010
Nice illustration of the current state of research into one of the most widely consumed drugs in human history. "Using a hallucinogen increases chances of having hallucinations." Awesome. What about the fact that it stimulates neurogenesis? Very weak article.
marjon
1 / 5 (8) Aug 19, 2010
It will fun to watch the pot heads attack any research that suggests their drug is dangerous.
zslewis91
3.7 / 5 (3) Aug 19, 2010
garbage. utter rubbish
zslewis91
5 / 5 (3) Aug 19, 2010
It will fun to watch the pot heads attack any research that suggests their drug is dangerous.


"research", faulse, and untrue...there is sufficient research that argues the opposite..and..a single atom has the potential to "harm", like-wise a fly, and a USB Port, a bit of paper. a plastic bag..."harm"? Harm is a relative term...marjon
Skeptic_Heretic
4.6 / 5 (9) Aug 19, 2010
It will fun to watch the pot heads attack any research that suggests their drug is dangerous.

Nah, all drugs are dangerous, including aspirin. Side effects typically don't strike 100% of the user base.

My father worked in law enforcement and said to me "there are some people who shouldn't smoke marijuana. Whether it is their genetics, personality, or attitude, it doesn't affect them the same way as it does most people. They lose a bit of themselves."

I agree with him. Some people have little to no ill effects from use, others go utterly out of their minds. Without allowing research on the drug, we'll never know why.
tjcoop3
3 / 5 (2) Aug 19, 2010
Gotta wonder about their conclusions. It seems as though they had preconceived notions about cannabis harm.
How is it that they know that having auditory hallucinations is harmful much less psychotic. The issue should be whether cannabis causes one to harm others.
Caliban
4.1 / 5 (7) Aug 19, 2010
Agreed, there, Skeptic.
But the portion of users that suffer any significant level(enough to cause them to act to defend against some perceived"threat")of psychosis is -or at least appears to be- very small.

Speaking from personal experience, though, and as one who has suffered some bouts of anxiety subsequent to use, it is important to point out that I've also had quite severe effects from drinking coffee -at least as severe as from smoking, so there you have it- everyone does respond differently, regardless of the drug/substance, and the same holds true not just for drugs, but for anything that is incorporated into the body, through direct or indirect means.

The unfortunate likely effect of this study will be to further demonize what, to all appearances, is a quite benign, and very possibly a strongly multi-therapeutic agent. I suspect we'll see tons more "research" claiming harmful effects, as the push for leagalization gains ever more steam socially/politically.
bottomlesssoul
5 / 5 (7) Aug 19, 2010
I've been a heavy user for 30 years and lead a successful, well educated and peaceful existence. So far for myself the only drawbacks are cost and that the drug is usually delivered by smoking. And I know many many life long chronics.

However I know a number of people who get really messed up by it. Most of them have other underlying conditions that predispose them to psychosis. But some seem fine to me yet reliably have bad experiences with it.

Like any potent molecule used in a complex genetic engine that varies across a species, the picture is very complex indeed.
marjon
1.4 / 5 (9) Aug 19, 2010
I agree with him. Some people have little to no ill effects from use, others go utterly out of their minds. Without allowing research on the drug, we'll never know why.

But we should have government agencies telling us what is good for us or not? If individuals can and should decide for themselves, why shouldn't they have that same liberty in economic decisions?
Instead of laws being used to violate rights, the law should be used to prosecute violation of rights.
Caliban
4 / 5 (4) Aug 19, 2010
I agree with him. Some people have little to no ill effects from use, others go utterly out of their minds. Without allowing research on the drug, we'll never know why.

But we should have government agencies telling us what is good for us or not? If individuals can and should decide for themselves, why shouldn't they have that same liberty in economic decisions?
Instead of laws being used to violate rights, the law should be used to prosecute violation of rights.


Mongo- are you high?
Weightgain4000
5 / 5 (5) Aug 20, 2010
Their is lies, damn lies and then their is statistics!
With any "carefully" worded survey Im sure you can come to any collusion your heart desires!
This research seems along the same lines

Keele University Staffordshire,
http://www.ncbi.n...19560900

According to research of scientists at Keele University in Staffordshire, UK, the incidence (the number of new diagnosed cases)of schizophrenia in the years 1996 to 2005 does not support the hypothesis that cannabis use increases the risk for the development of schizophrenia or psychosis. For this study an analysis of data from 183 practices in England, Wales, Scotland and Northern Ireland was
conducted. The study cohort comprised almost 600,000 patients each year, representing approximately 2.3 per cent of the UK population aged 16 to 44.
burn
Palli
Aug 20, 2010
This comment has been removed by a moderator.
Palli
5 / 5 (1) Aug 20, 2010
oh yeah, forgot...Legal like alcohol! (or carrot juice)
Ravenrant
1 / 5 (1) Aug 20, 2010
Since it doesn't cause hallucinations as the article states (and neither does anything else), this article is bogus. Must be funded by Fox.
marjon
Aug 20, 2010
This comment has been removed by a moderator.
Skeptic_Heretic
not rated yet Aug 20, 2010
Decriminalize ALL drugs. That is the only rational path. Note I did not say legalize. If the governemnt taxes any drug, it must encourage and support its use.

For once I'm in full agreement with your entire statement.
Shootist
1 / 5 (3) Aug 20, 2010
Since it doesn't cause hallucinations as the article states (and neither does anything else), this article is bogus. Must be funded by Fox.


Perhaps I misunderstand.

Nothing causes hallucinations?
Thrasymachus
5 / 5 (2) Aug 20, 2010
Marijuana IS an hallucinogen, it's just not a very strong one. But then, it doesn't take much to set some people off. I would prefer full legalization, including taxation, rather like is done with alcohol. The notion that a government must promote what it taxes is patently ridiculous.
marjon
1 / 5 (1) Aug 20, 2010
Marijuana IS an hallucinogen, it's just not a very strong one. But then, it doesn't take much to set some people off. I would prefer full legalization, including taxation, rather like is done with alcohol. The notion that a government must promote what it taxes is patently ridiculous.

It is not when the state needs more money.
It promotes state lotteries and casinos why wouldn't they promote other vices they tax for more revenue?
Skeptic_Heretic
not rated yet Aug 20, 2010
The notion that a government must promote what it taxes is patently ridiculous.
Actually I think Marjon has this one dead on the money.

If you look at the tax code in America it is used as a morality weapon.
Ravenrant
1.5 / 5 (2) Aug 21, 2010
Since it doesn't cause hallucinations as the article states (and neither does anything else), this article is bogus. Must be funded by Fox.


Perhaps I misunderstand.

Nothing causes hallucinations?


In the 70's and 80's my friends and I took almost every drug, including acid, peyote, mushrooms, etc, a few times. Neither I or anyone I ever talked to has ever had a 'hallucination' on anything (after careful questioning).

And the idea that MJ is a hallucinogen is ridiculous, as ridiculous as when it was called the killer weed.
Shootist
2 / 5 (4) Aug 21, 2010
Since it doesn't cause hallucinations as the article states (and neither does anything else), this article is bogus. Must be funded by Fox.


Perhaps I misunderstand.

Nothing causes hallucinations?


In the 70's and 80's my friends and I took almost every drug, including acid, peyote, mushrooms, etc, a few times. Neither I or anyone I ever talked to has ever had a 'hallucination' on anything (after careful questioning).

And the idea that MJ is a hallucinogen is ridiculous, as ridiculous as when it was called the killer weed.


My experiences suggests otherwise.
yyz
5 / 5 (3) Aug 21, 2010
I have to agree that this study seems rather lax in reporting its methods and seems to have a definite negative tone of warning in this article. As to methods:

"...to complete a questionnaire about their use of cannabis as well as a measure of psychotic symptoms."

More detail about how the questions are worded and what specific test was given for psychotic symptoms would be appreciated. Also, no hard numbers as to the stats themselves, just statements with qualifiers. Was there any screening of participants for diagnosed or possible undiagnosed psychiatric disorders prior to first use? At least Weightgain4000 linked to a more rigorous study of a much larger sample size. Between the two, I'd have to go with the latter.
Givemhell
not rated yet Aug 21, 2010
"psychotic" means abnormal condition of the mind, and is a generic psychiatric term for a mental state often described as involving a "loss of contact with reality". well put your mind on top of the drug and you might not have a loss of contact with reality
Thrasymachus
5 / 5 (1) Aug 21, 2010
What actually happens, and what has to happen, with regard to the tax code, are two different things. I prefer outright legalization to decriminalization because I would rather there be licensing and regulation of production to ensure purity of the product, fairness of the marketplace, and ensure minors don't get their hands on it as easily.
Cheerio
not rated yet Aug 21, 2010
You experience hallucinogenic phenomena from smoking cannabis? GET OUTTA TOWN.
marjon
1 / 5 (2) Aug 21, 2010
What actually happens, and what has to happen, with regard to the tax code, are two different things. I prefer outright legalization to decriminalization because I would rather there be licensing and regulation of production to ensure purity of the product, fairness of the marketplace, and ensure minors don't get their hands on it as easily.

So we will a government agency that certifies the 'quality' of pot to be sure customers get the most high for the buck? The FDA has done a wonderful job of certifying the safety of prescription drugs.
You don't see any conflict of interest on the part of the government?
Cheerio
5 / 5 (4) Aug 21, 2010
"And the idea that MJ is a hallucinogen is ridiculous, as ridiculous as when it was called the killer weed. "

Yeah, THAT is one of the most ignorant statements I've ever seen, on this website.

Seriously? You are going to deny that sometimes, people experience auditory (and sometimes, mild to severe visual) hallucinations after inhaling cannabis smoke?

Look - the definition of a 'hallucination' is the perception of something that isn't really there, be it auditory or visual.

Go stick yourself in a sense-dep tank for a couple of hours, and then get back to me on the stuff you 'heard'.

My point is, the brain kinda has a *tendency* to put us through stuff like that. I don't know why, maybe it's some kind of defense mechanism. Hell, maybe it just gets BORED, but either way -

pot can *definitely* help bring those mild auditory/visual hallucinations to the front row, no question.

Don't believe me? Maybe you should smoke some yourself, and find out. :)
Cheerio
5 / 5 (4) Aug 21, 2010
I feel I should qualify my previous statement, by saying that most people confuse 'hallucination' with stuff like seeing little smurfs jumping all over everything, or some ridiculously cliche, Hollywood 'drug trip'.

No, most of the time, pot doesn't do THAT, but anyone who knows what they're talking about when it comes to hallucinations will likely be the first to tell you that sometimes, (especially when you first start smoking pot, before your brain has a chance to deactivate dopamine receptors) you will see or hear things that do not exist, outside of your mind. Most of the time, however, you can easily make that distinction.

I've been down the road a couple of times, and I've seen a lot of drugs. The reaction this article seeks to illustrate is, in my experience, extremely rare (I've seen exactly one person who couldn't tell the difference between her imagination, and reality, on pot, although in hindsight, I think she was doing it for attention).
Cheerio
5 / 5 (3) Aug 21, 2010
"psychotic" means abnormal condition of the mind, and is a generic psychiatric term for a mental state often described as involving a "loss of contact with reality". well put your mind on top of the drug and you might not have a loss of contact with reality


Yeah, and 'hallucination' means 'perception without stimulus', but does Average Joe Internet Surfer know to make that distinction? Whoever wrote this article is either extremely careless with words, or is in somebody's pocket.
Burnerjack
3.7 / 5 (3) Aug 21, 2010
I have been around weed for about 35 yrs and have known MANY users. As far as halucinations go, I'm not sure those who experienced them would have in either case, smoking or not. This whole article remi nds me of "Reefer Madness", a most absurd movie about the "evils" of weed.
What I have observed is a predisposition for daydreaming, not being as "industrious" as one may have been otherwise. I also have noted a predisposition to want to "get along" with others.
The third observation is in some people, is a reduced ability at analyical thinking and problem solving. If you're "pretty smart", fine, else, not so much. So,those who have a more difficult time sorting out life's debacles may be better off without it. Those prone to violence,etc. may be better off with it.
Legalization, IMHO, needs to be looked at with a Risk/Reward viewpoint. Listening to Law Enforcement personnel who feel threatened with the repeal of any law should be viewed in that context.
Skeptic_Heretic
not rated yet Aug 21, 2010
So we will a government agency that certifies the 'quality' of pot to be sure customers get the most high for the buck? The FDA has done a wonderful job of certifying the safety of prescription drugs.
You don't see any conflict of interest on the part of the government?

Oh, I see a huge conflict of interest.

Simply look at what they did to tobacco. Due to government interference tobacco has become more addictive, more deadly, and more available to children.

It's rather distasteful to have the government in the substances industry. Again, Marjon, we agree.
Neophile
5 / 5 (2) Aug 22, 2010
I experience strong psychedelic sensations, bordering on hallucinations and a strongly negative worldview when I smoke pot. Which is why I don;t smoke pot. I think that my experiences are in the minority though. Regardless, I support legalization of all drugs. People should be able to do whatever they choose to their own bodies.
Weightgain4000
5 / 5 (3) Aug 22, 2010
@yyz thank you for your comments, I dislike these types of survey/research as they are often quite bias but are great for creating headlines

There is a large amount of research similar to the link I included above however this is often conveniently forgotten when it comes to election time or poll ratings :(

National Institute on Drug Abuse (NIDA) found marijuana use caused no significant increase in Mortality Marijuana Use and Mortality. American Journal of Public Health. Vol.87 No. 4, April 1997. p. 585-590. Sept. 2002.
http://www.ncbi.n...nalpos=2

More Study Links
http://www.drugpo...tsmyths/

dtxx
2 / 5 (4) Aug 22, 2010
The word hallucination implies that the person having the experience is aware that what they see/hear/etc. is not real.

Deliriants such as Belladonna or Datura are much closer in effect to the definition most people think of for hallucination. You will see your dead relatives and you will believe them to be 100% real, for example. Someone taking LSD, even at high doses, would not be susceptible to delirium anything like what benadryl would do.
Skeptic_Heretic
not rated yet Aug 22, 2010
The word hallucination implies that the person having the experience is aware that what they see/hear/etc. is not real.

Deliriants such as Belladonna or Datura are much closer in effect to the definition most people think of for hallucination. You will see your dead relatives and you will believe them to be 100% real, for example. Someone taking LSD, even at high doses, would not be susceptible to delirium anything like what benadryl would do.

If we're going to be all hung up on mild hallucinogenics then we'd need to treat activities that lead to similar occurance that are non-substance based as well.
Palli
5 / 5 (2) Aug 22, 2010
Quoting article:

Those who used the drug more frequently were at a greater risk still of experiencing such hallucinations, and heavy use also increased the risk of having delusions such as believing that someone was reading their mind.

Reading their mind? really? is this quoting a single test case, a direct question from the psycho test or an "explanation" from the author?
Did you notice the whole article has only three decimal digits in it, side by side, showing the number of students asked to complete a questionnaire.
Did all of the 334 persons participate?
There are no numbers describing any actual output of this "research", only free flowing spew from the author.
My previous post was pulled for being off-topic, This article seams to be off topic and misleading like many of you guys have pointed out.

I find this video clip (3:35) to complement this article very nicely, especially the guy in the tank!
http://www.youtub...embedded
Skeptic_Heretic
Aug 22, 2010
This comment has been removed by a moderator.
Tristan_Caley
5 / 5 (1) Aug 22, 2010
The article does not state whether the hallucinations occurred during use of cannabis or in the hours of sobriety in between highs. That is a HUGE distinction. I know many people who smoke medicinal marijuana (and do not really need it) and while they are high they often experience strange sensations of the nature described by this article. But when they aren't smoking it, or after they've come down from the high, they experience nothing of the sort.

This is junk science at best, since it doesn't take in to account the fact that many college age students who smoke weed also do other drugs such as tobacco, or alcohol. Those also affect how the mind perceives reality, and for much longer than THC does, so who's to say they are not playing major roles in any reported psychotic symptoms?