Mental Health & Suicide

Mental illness, psychotic symptoms, suicidal thoughts

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Almost half of the marijuana business in legalised jurisdictions is now in highly potent cannabis concentrates – edibles, dabbing (smoking highly concentrated THC) and vaping. The average psychoactive component of cannabis (THC) of all tested flower last year in Colorado was 19.6%, and the average potency of concentrated extract products was 68.6%. Potency rates of up to 95% have been recorded.

The 2% THC ‘woodstock weed’ has been replaced by popping a handful of gummy bears containing 10 times the legal limit of THC per serving, or a 90% THC dab.

This is definitely not your parent’s pot.

But with increased potency comes increased health risks, including mental illness, psychotic symptoms, suicidal thoughts among teens, respiratory problems, and a greater likelihood of addiction. And addiction is exactly what Big Marijuana wants.

Another claim made by drug advocates is “Nobody has ever died from marijuana.”

This is partly true. Nobody has ever died (that we’re aware of yet!) from an overdose – but what about the effects of getting stoned.  Remember – nobody has ever overdosed from tobacco and died, but we don’t say that tobacco is not harmful to our health or hasn’t killed anyone.

The real concern is the effect on mental health and suicide ideation. Marijuana has a variety of other interactions with mental health. Suicidal thoughts can come on very quickly while under the influence in individuals who were not previously suicidal. The suddenness of suicidal ideation means that intervention may not always be possible. 

A study published in the American Journal of Psychiatry (July 2019) further links the use of marijuana with the onset of severe mental illness such as psychosis and schizophrenia. The study followed over 7,600 individuals for a mean of 84 months. Among these, the cumulative risk for progression to schizophrenia was 11.3%. The risk for onset of mental illness was highest among marijuana users and lowest for alcohol abusers.

“Marijuana killed my soul and ruined my brain”

Sally’s son, Andy, committed suicide after becoming addicted to marijuana. In his suicide note, he said “marijuana killed my soul and ruined my brain.”

The Truth about Marijuana

Colorado toxicology reports show the percentage of adolescent suicide victims testing positive for marijuana has increased.

The percent of suicide incidents in which toxicology results were positive for marijuana has increased from 14% in 2013 to 23% in 2017 (Rocky Mountain High Intensity Drug Trafficking Area 2019)


2019 Colorado toxicology reports show the percentage of adolescent suicide victims testing positive for marijuana continues to increase. Between 2011 and 2013, 20.7% of suicide victims between the ages of 10 and 19 tested positive for marijuana (compared with 12.7% who tested positive for alcohol). By 2014-2016, 22.4% tested positive for marijuana (compared with 9.3% for alcohol) (Colorado Department of Public Health and Environment, 2019).

This disturbing trend is, unfortunately, not surprising, as daily marijuana use among youth who begin before the age of 17 significantly increases the risk of suicide attempts. Researchers led by the National Drug and Alcohol Research Centre at the University of New South Wales (and including New Zealand researchers) analysed results of three large, long-running studies from Australia and New Zealand involving nearly 3,800 people. Teenagers who start smoking cannabis daily before the age of 17 are seven times more likely to commit suicide, a study has found.

Massey University drug researcher Dr Chris Wilkins warned,

If you’re using high potency, using daily or if you’ve a history of mental illness or drug addiction it can have serious health problems bringing on mental illness or further addiction.”

And University of Queensland Centre for Youth Substance Abuse professor Wayne Hall said legalising the drug would likely have the most significant impact on current users. If cannabis was made more affordable and easier to access, then consumption would increase, like any commodity.

NEW STUDY: Nov 2019 – More than a third of people who experienced psychosis with cannabis use later transitioned to schizophrenia, according to a systematic review and meta-analysis published online in Schizophrenia Bulletin. Similarly, schizophrenia transition risk among people who experienced psychosis from hallucinogen or amphetamine use was also considerable. “These findings have important implications for mental health care and services. Substance-induced psychoses are common reasons for seeking mental health care.” The meta-analysis spanned 50 studies which provided 79 estimates of transition to schizophrenia among 40,783 people with substance-induced, brief, or atypical psychoses. Some 25 of the studies, which included 34,244 people, had substance-specific estimates. Overall, 25% of people who experienced substance-induced psychosis transitioned to schizophrenia, researchers reported. The rate of transition for people who transitioned to schizophrenia after brief, atypical, or not-otherwise-specified psychoses was 36%. The highest rates of transition to schizophrenia were associated with cannabis-induced psychosis (34%).

Deaths associated with marijuana consumption

Exchange student Levy Thamba (19) falls to death in Denver after eating marijuana cookie – April 2014

Luke Goodman (23) fatally shoots himself after eating 5 marijuana candies – Mar 2015

Daniel Juarez (18) Stabbing Suicide Latest Death Linked to Marijuana Intoxication – May 2015

Marc Bullard, 23, Colorado

Brant Clark, 17, Colorado

Shane Robinson, 25, California

Rashaan Salaam, 41, Colorado

Hamza Warsame, 16, Washington

Andy Zorn, 31, Arizona

Tron Dohse, 26, Colorado. Dohse’s death was determined to have been an accident. Unable to find his keys, Dohse climbed up the apartment building and fell.  The toxicology report 27.3 ng. of marijuana in his blood, but no other drugs or alcohol in his system.  As his sister told CBS, she believes marijuana impairment led her brother to make poor decisions the night of his death.

“Neither my husband nor I ever touched illegal drugs, or used pharmaceuticals. Parents who think they raised their kids sensibly, spent quality time with them and modeled a healthy lifestyle need to be forewarned. Our kids are surrounded by a culture of pot. No family is safe.”
Lori Robinson – Shane’s mum



Here in New Zealand, a toxicology test revealed the pilot of the balloon that crashed in Carterton in 2012 had cannabis in his system. Pilot Lance Hopping, 53, and 10 passengers died when the hot air balloon collided with power lines and caught fire near Carterton. Although there was no proof the pilot had used cannabis before the flight, statements from people who knew him, as well as post-mortem forensic tests, revealed that he was a weekly cannabis user and the long term effects of using the drug could have had an “effect on his perception and thinking”.


And don’t forget the effect on driving. Since recreational marijuana was legalised in Colorado, marijuana related traffic deaths increased 151%, more than doubling from 55 in 2013 to 138 people killed in 2017. According to AAA, Washington State experienced a doubling in drugged-driving fatalities in the years following legalisation.

One Mother’s Story

Corinne Gasper’s 22-year-old daughter, Jennifer Hrobuchaka, was killed by a drugged driver in July 2012. “She was driving into work when she was hit by a man high on marijuana, racing through an intersection at 82 miles per hour into her passenger side,” Gasper said.

Since recreational marijuana was legalised, traffic deaths in which drivers tested positive for marijuana increased 109% while all Colorado traffic deaths increased 31% (Rocky Mountain High Intensity Drug Trafficking Area 2019)