August 20, 2004

Street Drugs and Schizophrenia

Cannabis use in Australia is at an all-time high and is putting heavy users at risk of experiencing schizophrenia, a conference in Melbourne has heard. The National Cannabis and Mental Illness Conference in Melbourne yesterday heard Australian rates of use were higher than the US, UK and much of Europe and that one in 10 regular users would become dependent on the drug.

Professor David Castle, from the Mental Health Research Institute, said there was no doubt cannabis use could worsen mental illnesses like schizophrenia.

But it was more difficult to say how many people would never have become ill if they had not used cannabis, Professor David Castle said.

The former head of the National Drug and Alcohol Research Centre, Dr Wayne Hall, said cannabis use had steadily increased since the 1970s.

"We are probably a bit higher than the UK and the US," he said. "We are a lot higher than the Netherlands, for example, which is a favourite comparison given their policies on cannabis."

Mental Health Research Institute professor David Castle described cannabis
as the straw that breaks the camel's back, saying there appeared to be a link between the drug and psychosis, but only for those already predisposed towards
the illness.

"Most people who use cannabis and get psychosis have an underlying vulnerability," he said.

There was consensus among the experts that occasional users who did not have a predisposition towards mental illness were unlikely to suffer long-term effects. But regular, heavy use could affect people's jobs and relationships.

Cannabis authority Professor Markus Leweke, of Cologne University in Germany, said cannabis was three times stronger than it used to be.

"Cannabis today is totally different than cannabis 20 or 30 years ago," he
said, pointing to a boost in the active ingredient, tetrahydrocannabinol.

Richard McLean, 31, had a cannabis dependency that he believes contributed to the schizophrenia he experienced for five years.

Mr McLean said he stopped using cannabis when he became psychotic, but the
symptoms continued.

"My feeling is I did have a predisposition and my stresses and my use of marijuana led to my psychosis," he said.

Mr McLean said his illness caused pain and confusion for his family, friends and himself.

"It's just a tragic situation that I had to go through years of losing friends; I had to go through years of losing job opportunities, being depressed and navigating my way through the mental health system," he said.

PEOPLE concerned about drug-induced psychosis can call the SANE Australia
help line on 1800 688 382.


has there been any info on developing schizophrenia in the offspring of fathers using mariuana around time of conception

Posted by: sue at August 30, 2004 10:18 PM

Is there any evidence to suggest that the younger a person is when they start to use cannabis, the more likeley they are to develop psychotic illnesses? If so, if they stop usong cannabis, how likely are they to recover?

Posted by: Jane at August 31, 2004 11:55 AM

I am also interested in schizophrenia development in offspring of fathers who were regular marijuans users.

Posted by: cindy at August 31, 2004 05:41 PM

The article is quite correct - if you inspect the OECD statistics, you find that Australia has one of the highest rates in the developed world for Marijuana use. It is also interesting to note New Zealand's extraordinarily high usage rate. These statistics can be approached at

Posted by: Mary at September 6, 2004 02:49 AM

Excuse me,
But I'm a regular user of cannabis and personally I think that article is, pardon me, full of Crap! There is plenty of research done that points the irregular patterns of brain cells whic form LONG before BIRTH! Using cannabis may trigger a psychotic episode but only if you already have the disease since the whomb. If your looking for something to blame your condition on MR. "szadmin" I suggest you lay off the Cid because its getting to your head.
OH yeah, and I live in Canada. Developing the highest rates in the world for Mariuana use, BITCH!

Posted by: Unamous at December 11, 2006 06:55 PM

This really doesnt tell me about what drugs people take for schizophrenia its just about the risks i want to know what drugs people should take.

Posted by: Katrina at January 26, 2007 08:07 AM

How does cannabis make you a schizophrenic? You must not have the right evidence to what you are talking about.When was the last time you ever heard of someone devoloping schizophrenia from cannabis?My point exactly this posting of risks is a load of shit!

Posted by: nothing at January 26, 2007 08:17 AM

Cannabis can trigger schizophrenia, by extended heavy long term use, and by the mixture of LSD use along side. Sufferers from ADD or other such disorders are prime candidates. Paranoia that can strike any grass smoker is the start to unraveling this mystery. The chemical property that interacts with the brains fear and adrenalin area within the THC itself is the root cause after years of abuse. After years of heavy use, the smoker can become stuck on a certain paranoia, therefore giving birth to a psychiatric problem. With some people it only takes months for the dope to take its toll. This is why the damn stuff is illegal. There is one answer to the legalization question, and that is everyone is different, and grass effects everyone unprictably different. Why is booze legal, it doenst matter if your schizophrenic, or if your the leader of a nation, that liquid shit does one thing, make you spin, and barf. But alcohol is not good for schizophrenic people either. The key is stay clean and sober..

Posted by: timbuck2 at December 2, 2007 09:51 AM

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