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Researchers claim cannabis increases the risk of psychosis - just as Canberra liberalises marijuana

by BRETT LACKEY FOR DAILY MAIL AUSTRALIA, posted 04 10 2019

• Briefing paper for Health Minister links cannabis to increased mental disorders 
• The report was prepared following the ACT passing new marijuana laws 
• The new laws allow small amounts of cannabis for personal use up to 50 grams 
• Health Minister issued reminder that it is still illegal under commonwealth law 

 Regular use of cannabis doubles the risk of psychotic symptoms including schizophrenia and is strongly linked to anxiety disorders, depression, and psychosis, a report prepared for Health Minister Greg Hunt reveals. 

The briefing paper, triggered by the recent passing of marijuana laws in the Australian Capital Territory, says that adverse mental health issues have 'broadened considerably' as the drug has become decriminalised. 

The three page brief, obtained by The Weekend Australian, points to research from the US state of Colarado, Australia, Canada that found daily or near daily use of cannabis was associated with the development of a psychotic disorder.   

'The evidence base regarding adverse health effects linked to cannabis use has broadened considerably since the gradual decriminalisation, and in some cases legalisation, of the substance in certain international jurisdictions,' the department says.

'Adverse health outcomes as a result of regular cannabis use are not limited to mental health and psychotic symptoms.'

The reports notes a 2018 Canadian Medical Association Journal report found an overwhelming volume of evidence pointing to the biological impacts of regular cannabis use including brain changes, adverse cognitive outcomes, negative pregnancy outcomes and testicular cancer. 

The briefing paper also claims the main active ingredient in marijuanana. tetrahydrocannabinol, increased 30 per cent in strength form the mid 1990s to early 2000s. 

The new laws passed in the ACT allow private houses to hold up to four plants and individual adults to posses 50 grams of cannibis. 

ACT Chief Minister Andrew Barr supported the legislation and the federal government now wants an explanation. 

Health Minister Greg Hunt said he was 'deeply concerned about the very real risks cannabis can pose to physical health and, in particular, to mental health'. 

'This is why cannabis is a highly regulated drug, Legalising recreational cannabis is dangerous and medically irresponsible.' 

The ACT law takes effect from January 31. 

A spokesperson for the ACT government said the laws relate to personal use of marijuana and is not the same as large scale decriminalisation seen in places such as Colarado. 

Attorney-General Christian Porter is expected to review a final copy of the legislation, when published next week, before deciding if the federal government should override the law. 

He also issued a reminder that owning any amount of the drug is still an offence under commonwealth law.