Health - Cannabis,tobacco and schizophrenia

[vinylmesh]

SWIM is sick of hearing in the media; "cannabis causes schizophrenia".

SWIM was reading about how between 75 and 90% of people with schizophrenia were tobacco users.We know for a fact that tobacco can bring on schizophrenia.We even know the mechanism by which this works (nicotine causes a long term increase in dopamine levels which is linked to schizophrenia). I'm quite sure cannabis doesn't affect dopamine (if it did, it would be mega-addictive,like tobacco).

If someone is a heavy user of cannabis the chances are they also smoke tobacco aswell (whether it be mixed in with joints or in cigarette form).

Now it's possible (nay, probable) that cannabis potentiates the schizophrenia-inducing properties of tobacco. But surely it's the tobacco that's to blame and not the cannabis.


It's suprising how none of the studies i've read considered tobbaco smoking in their conclusion.

what yiz think?

[Graduisic]

swim would agree with something that panthers said in another thread about using drugs and mental illness, it isn't causing something that wasn't there to begin with already.

[mickenator]

Swim avoids smoking canabis due to the fact that it agrivates there drug induced pshchosis but swim feels that it is not the cause for it. Just don't take it as it makes swim worse, but swims problems where already there and have been since being a child.

[vantranist]

Originally Posted by vinylmesh

SWIM is sick of hearing in the media; "cannabis causes schizophrenia".

SWIM was reading about how between 75 and 90% of people with schizophrenia were tobacco users.We know for a fact that tobacco can bring on schizophrenia.We even know the mechanism by which this works (nicotine causes a long term increase in dopamine levels which is linked to schizophrenia). I'm quite sure cannabis doesn't affect dopamine (if it did, it would be mega-addictive,like tobacco).

If someone is a heavy user of cannabis the chances are they also smoke tobacco aswell (whether it be mixed in with joints or in cigarette form).

Now it's possible (nay, probable) that cannabis potentiates the schizophrenia-inducing properties of tobacco. But surely it's the tobacco that's to blame and not the cannabis.


It's suprising how none of the studies i've read considered tobacco smoking in their conclusion.

what yiz think?

SWIM believes its actually the lack of dopamine in the brain thats linked to schizophrenia. Not the increase of it. Perhaps SWIY meant tobacco causes longterm lack of dope instead of increasing it?

I am not an expert on this but I believe theres a lot more too it than you're summing up.

Low levels of dopamine Is linked to schizophrenia but still too little is known about it to make an observation like that. Who said thats the only contributing factor to schizophrenia? There can be so many other things that Nicotine doesn't even touch that Marijuana does. Remember THC is partially a psychedelic drug, which are also well know for causing disruptions.

THC and other cannaboniods may not directly act on the limbic system but that doesn't mean it has no effect on dopamine.

When comparing the addictiveness of nicotine and Cannaboniods, I believe the two are quite different. Nicotine is more of a physical addiction, and Marijuana would produce more of a psychological addiction. However please keep in mind both are capable of producing both physical and psychological dependency and often they will.

I believe Dopamine is more Linked so psychological dependency then physical dependency. Please correct me if i'm wrong (I don't know much about nicotine or pharmacology) But nicotine has a number of effects in the brain, increased amounts of dopamine is just one of them and he isn't even sure if thats whats nicotine is known for as goes addictiveness, surely its responsible for some of its psychological dependency however other unrelated effects it carries out on our brains May produce the more well known side of nicotines dependency (Physical)

PS. "I'm quite sure cannabis doesn't affect dopamine (if it did, it would be mega-addictive,like tobacco)."

I am willing to bet Marijuana has more indirect effect on dopamine than Nicotine does directly.

Does anyone actually know? SWIM is very interested.

[Ontherooftops]

You're a good bit off on that one, SWIVinylmesh, as dopamine is why marijuana is intoxicating.

Cannabis or THC particularly, blocks the release of dopamine inhibitors. With the inhibitors no longer active in the synapse, dopamine is then able to flow freely to our dopamine receptors.

[vinylmesh]

No i'm quite sure schizophrenia is caused by too much dopamine.
That's why antipsychotics (dopamine antagonists) are used to treat it.

http://en.wikipedia.org/wiki/Dopamin..._schizophrenia

Also nicotine actually makes the brain more sensitive to dopamine in the long-run.

http://en.wikipedia.org/wiki/Nicotine#Dependence

Also while THC does have an effect on dopamine, it's indirect and not very great. Just like the way they say alcohol affects dopamine.

Trust me, if THC produced a noticeable increase in dopamine SWIY would know all about it.

I'm not saying cannabis is harmless. I'm just saying that maybe it's not fully to blame. Maybe it works in synergy with the tobacco. Maybe we should be strongly encouraging people to not use tobacco in their joints..

[vantranist]

Interesting artical the first one.

SWIM can actually feel a domapine rush when he smokes a powerfull sativa, no where near that of cocaine, or meth, and its even harder to notice it with all the other effects mixed in there, but swim insists theres a bigger push with THC on dopamine than hes felt with any other drug hes done besides cocaine meth and MDMA. he was a meth and coke addict and lives for that euphoric calmness, that feeling that everything in your life is ok which these drugs provide, he is used to that feeling and can pick up the slightest traces of it when he feels it.

[tweakerman]

Swim believes that marijuana and other street drugs are linked to a significant risk of schizophrenia. Many studies have been done in Europe, Australia and Sweden which back up this theory.

From the British Medical Journal: "Cannabis use is associated with an increased risk of developing schizophrenia, consistent with a causal relation. This association is not explained by use of other psychoactive drugs or personality traits relating to social integration."

http://bmj.bmjjournals.com/cgi/conte.../325/7374/1199



A study done by Swedish researchers interviewed 50,000 in the Swedish Army and then again later in life about their drug use. They found that if those who were heavy marijuana users at age 18 were 600% more likely to develop schizophrenia than those who didn't use marijuana.

http://bmj.bmjjournals.com/cgi/conte.../325/7374/1199

It has been shown that marijuana increases the risk of schizophrenia in those who have a predisposition towards schizophrenia. Those with a family history of mental illness are considered at high risk of developing schizophrenia anyway. Using marijuana as a teenager can flip the switch so to speak, causing the schizophrenia to develop as an adult.

Andrew Campbell, of the NSW Mental Health Review Tribunal (Australia) says that using heroin is safer than marijuana. This conclusion was from a study he did which found that 4 out 5 patients in a psychiatric hospital suffering from psychosis used marijuana as a teenager.

Doctors at the Social, Genetic, and Developmental Psychiatry Centre, Institute of Psychiatry, King's College London say that there is a direct link between teenage marijuana use and adulthood psychosis: "Recent evidence documents that cannabis use by young people is a modest statistical risk factor for psychotic symptoms in adulthood, such as hallucinations and delusions, as well as clinically significant schizophrenia. The vast majority of cannabis users do not develop psychosis, however, prompting us to hypothesize that some people are genetically vulnerable to the deleterious effects of cannabis."

http://www.ncbi.nlm.nih.gov/pubmed/1...?dopt=Abstract

Cannabis impacts neurotransmitters that regulate how arousal and stress are managed in the brain. Cannabis takes a long time to metabolize, and can quickly build up to high levels in the body. Once you get to this point, there is a real risk of depression or schizophrenia being triggered. Meaning that the more you use, the higher the level in your body, the greater your risk.

Although most people with shizophrenia (up to 80%) smoke tobacco researchers do not believe that tobacco actually causes schizophrenia to develop. Smoking does release dopamine in the brain, so it can be used to self medicate. It can reduce the negative symptoms of schizophrenia such as apathy and low self-esteem. It is also thought to reduce the side-effects of the treatment drugs. So the mentally ill are more likely to smoke because of the positive effects and perceived benefits of smoking. Smoking does not increase the risk of schizophrenia.

http://www.mydr.com.au/default.asp?article=3076

Smoking can actually reduce the risk of developing schizophrenia. Referring back to that Swedish study Swim mentioned earlier, they also studied the effects of smoking tobacco at adolescence. The findings were that smoking cigarettes could prevent schizophrenia. Men who smoked at age 18 were 10% less likely to develop schizophrenia. Plus the more they smoked the lower their risk became.

http://www.ncbi.nlm.nih.gov/pubmed/1...=AbstractToday


There are over 30 published papers linking marijuana to schizophrenia or other mental disorders. The increase in evidence is likely due to the increased potency of marijuana. A review by the British Lung Association says that the cannabis available on the streets today is 15 times more powerful than the joints being smoked three decades ago.

At Trimbos-instituut, Centrum Preventie en Kortdurende Interventie, Postbus in the Netherlands they studied the relationship between marijuana and schizophrenia. Their research says that marijuana is a probable causative factor in the development of schizophrenia. Cannabis use, they say, along with other risk factors increase the risk of psychosis and schizophrenia.

http://www.ncbi.nlm.nih.gov/pubmed/1...?dopt=Abstract


"In 1999 Terry Hammond's son, Steve, developed schizophrenia. Terry believes that Steve's condition was brought on by his cannabis use." From the BBC News article entitled "My son and cannabis". You should read the story of a parent who believes his son's marijuana use caused his schizophrenia.

http://news.bbc.co.uk/2/hi/programme...ma/4104744.stm


"Cannabis generally makes psychotic symptoms worse and lowers the chances of recovery from a psychotic episode. People with a psychotic illness such as schizophrenia who use such drugs experience more hallucinations, delusions and other symptoms; they have a higher rate of hospitalization for psychosis; treatment is generally less effective; and recovery is more difficult."

http://www.mydr.com.au/default.asp?Article=2343



In conclusion, Swim has his own personal experience to share. Swim used marijuana heavily at age 18. Swim received a diagnosis of schizo-affective disorder after years of struggling with imaginary voices, low self esteem, difficulty concentrating, and depression. Swim uses meth which reduces the positive symptoms of schizo-affective disorder, namely psychosis. Swim is also on medication for the disorder. Whenever Swim smokes pot the voices return, regardless of what medication he has or has not taken. Swim is convinced that his illness was triggered by marijuana. The schizophrenia was probably there already, but marijuana turned it on. If Swim did not smoke marijuana at age 16-19 he probably would never have developed schizophrenia and his life would have been completely different without his imaginary friends.

Reputation Comments on this post:

	Well researched & referenced post, nicely refuting some of the tosh that comes before it!
	Excellantly researched post!

[vinylmesh]

sorry i was gonna post something but then i read more of the thread.

I'm probably wrong, but it's good to challenge assumptions once in a while (i realise there's probably some very educated people on this site who'd know more than me).

ah well, what can ya do. I might be somewhat right though....... if the dopamine hypothesis of schizophrenia is true.

[Cryptic Concoction]

We do not "know for a fact that tobacco can bring on schizophrenia." Firstly, the mechanisms by which schizophrenia is produced are far from understood. Thus, it is absurd to suggest that anything is "known for a fact" concerning its causes. Twin concordance rates suggest that there is a strong genetic component, some have proposed that prenatal virus exposure may potentiate it, and it is thought that increased dopamine levels or receptors may be involved in schizophrenia.

The fact that there are very high smoking rights among the schizophrenic population is purely a statistical correlation. It can not be asserted that schizophrenia is caused by tobacco or even that tobacco potentiates schizophrenia. My explanations have been postulated for this statistical correlation, including that tobacco may serve a "self-medicating" mechanism, as it seems to confer an increase in focus, alleviating the disordered thought process of schizophrenics. However, none of these explanations have been whole-heartedly accepted, to the best of my knowledge.

It simply cannot be affirmed that tobacco mediates the effects of schizophrenia or causes it. That is absurd. The mechanisms through which schizophrenia are produced are very complex and seem to involve genetic, prenatal, postnatal, as well as neurophysiological factors.

Once again, the statistical correlation you have presented in no way even remotely suggests that nicotine is involved in the development of schizophrenia. The fact that nicotine affects dopamine and that it has hypothesized that dopamine may be an integral component in schizophrenia in no way establishes that nicotine can bring about schizophrenia. Furhtermore, the dopamine hypothesis is just that--a hypothesis. It should not be presented as an incontrovertible scientific fact.

If you can present conclusive scientific evidence that tobacco can cause schizophrenia or even bring latent schizophrenia to the fore, I will gladly recant my statements.

It is not understood how the symptoms of schizophrenia are mediated, so it certainly cannot be known that tobacco causes schizophrenia, and it would be even more farfethched to suggest that it is known how tobacco can "bring on" schizophrenia.

Cryptic Concoction added 1 Minutes and 22 Seconds later...

The sentence "My explanations have been postulated[...} should read "Many explanations have been postulated [...]"

[vinylmesh]

Yeah, i probably went overboard, hence me stating that i'm probably wrong in the last post.

However if people can accept that cannabis can cause schizophrenia when the rates are so much lower, then why can they not accept that nicotine may play even a tiny role. Given that a lot of daily cannabis smokers would smoke tobacco aswell.

If schizophrenia does indeed have an element of an overly sensitive reward system, and we know tobacco sensitizes the reward system (unlike most stimulants which de-sensitize it) and we know that some anti-psychotics work be antgonising the dopamine receptors, then i don't see how you could dismiss any possible link so casually.

[Cryptic Concoction]

I didn't dismiss any possible link; I merely stated that we cannot make assertions based on statistical correlations and insufficient research.

The same is true for cannabis. It would be rash to affirm without a vestige of a doubt that cannabis can cause latent schizophrenia to be triggered that would not have been elicited to the fore otherwise. We may speculate that it can increase the risk in those predisposed to schizophrenia based on the scientific research available, but it would be rash and brazen to assert it as incontrovertible fact.

Statistical correlations are often twisted and abused by the mainstream media and the government without a firm establishment of causality. There are always lurking variables to consider. Given the fact that the cause of schizophrenia and the underlying mechanisms remain relatively obscure, I think it is important that everyone exercise caution and restraint in formulating definitive conclusions.

I once saw an anti-gambling commercial stating that kids who gamble are five times as likely to smoke cigarettes. Did gambling cause these kids to smoke cigarettes? I highly doubt it, and there exists a throng of other variables to consider.