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Buddy T

Heavy Meth, Marijuana Users Risk Schizophrenia

By November 15, 2011

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A large-scale study of people hospitalized for substance abuse problems, but who had no persistent psychosis, has found that heavy methamphetamine and marijuana users are much more likely to develop schizophrenia than those who were treated for cocaine, opioids or alcohol. Meth and pot users are 1.5 to 3 times more likely to become schizophreniacs, researchers said.

Meth and marijuana users are 9 times more likely to develop schizophrenia than hospitalized patients with no substance abuse history.

Researchers in Japan have previously linked meth use to persistent schizophrenia-like psychosis, but until now, scientists in the United States had discounted the theory.

A Study of 42,412 Meth Users

Consequently, researchers at the Toronto Centre for Addiction and Mental Health analyzed records of patients admitted to California hospitals between 1990 and 2000 who were diagnosed with dependence or abuse of methamphetamine, marijuana, alcohol, cocaine or opioids. There were 42,412 people in the methamphetamine group and 23,335 in the marijuana group. None had ever been diagnosed with schizophrenia or psychotic symptoms before hospitalization. Their records were compared to a control group of patients who were hospitalized for appendicitis.

They found that heavy meth use was significantly linked to an increase in risk of developing schizophrenia and they confirmed previous research that linked heavy marijuana use to schizophrenia-like psychosis.

Risk Higher in All Drug Users

Compared to the control group, meth and marijuana users were 9.37 times more likely to later be diagnosed with schizophrenia. Compared to alcohol, cocaine and opioid users, meth and marijuana users were 1.46 to 2.81 times more likely to develop schizophrenia.

The risk of schizophrenia was higher in all drug users than in the appendicitis group.

The researchers said they do not understand how meth and marijuana work to increase the risk of schizophrenia.

"Perhaps repeated use of methamphetamine and cannabis in some susceptible individuals can trigger latent schizophrenia by sensitizing the brain to dopamine, a brain chemical thought to be associated with psychosis," Dr. Stephen Kish said in a news release.

Callaghan, RC, et al. "Methamphetamine Use and Schizophrenia: A Population-Based Cohort Study in California." The American Journal of Psychiatry 8 November 2011.

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November 16, 2011 at 7:55 am
(1) Justin George says:

Why combine marijuana and meth into the same statistic unless they have equal data and results? The one study listed was ONLY for meth. It appears this research is trying to find problems without explaining or sufficiently supporting them.

Several studies released over the past seven years have demonstrated the ability of the active ingredient in marijuana to provide protection to neurons against toxic molecules implicated in Alzheimer’s disease.
According to a 2004 study published in the very respectable Journal of Neurochemistry, “cannabidiol exerts a combination of neuroprotective, anti-oxidative and anti-apoptotic effects against beta-amyloid peptide toxicity, and that inhibition of caspase 3 appearance from its inactive precursor, pro-caspase 3, by cannabidiol is involved in the signalling pathway for this neuroprotection.”

A 2006 study by a whole different set of scientists published in the peer-reviewed journal Molecular Pharmaceutics appeared to support the earlier finding, noting “this study provides a previously unrecognized molecular mechanism through which cannabinoid molecules may directly impact the progression of this debilitating disease.” The authors note that cannabinoids appear to be more effective than the approved medications at treating the effects of Alzheimer’s on neurons in the lab.

November 16, 2011 at 11:48 am
(2) Molly McErik says:

“There were 42,412 people in the methamphetamine group and 23,335 in the marijuana group.”

It wasn’t just a study on meth users. There was also a marijuana group.

January 2, 2012 at 11:40 am
(3) cdcounselor says:

Regardidng your cellualr comment, you are probably a smoker but have you ever had 11 php level treatment s for pot becaeu you are addicted,those are young adults I treated for last 37 yrs., they would chose celluaalr damamge to addiction, like I woould have,had I never been able to enter recovery at a time when pot was less addictive

January 3, 2012 at 8:40 pm
(4) beatnuk says:

Lethal toxicity.
If 2 drinks is a “normal dose” of alcohol and 20 drinks is a “lethal dose” (consumed in one or two hours) then the normal dose of alcohol is only one tenth that of the lethal concentration. If 2 joints is a “normal dose” of marijuana and 20,000 joints is the lethal concentration, on the other hand, then the normal dose of marijuana is one ten thousandth of a lethal dose. Logical conclusion: marijuana must be 1,000 times more poisonous than alcohol!

Aches and pains after using
The most common withdrawal effect of alcohol is a terrible, flu-like headache. The pain emanates from the forehead, corresponding to the pre-frontal lobes of the human cerebral cortex. I’ve never had a “brain-ache” after smoking pot, so obviously, marijuana causes much more brain damage than alcohol!

People on alcohol, in my personal experience, are far more psychotic than people on pot. Only alcohol psychosis causes assaults, sexual offences, domestic violence, and murder. So, obviously, marijuana is much more dangerous than alcohol!

PS try googling “alcohol psychosis” — remember when pot was a “soft” drug because it wasn’t addictive like alcohol or heroine? Well, miraculously, after 4,000 of being a non-addictive drug, marijuana is suddenly addictive! Similarly, the phenomenon of alcohol psychosis is not the least bit controversial — it’s well-established in the medical literature. But suddenly, after 4,000 years, marijuana now causes psychosis. Hmmm.

The people who make ridiculous inflated claims about marijuana have never used the stuff or been around people who use the stuff, so they project what they know from their own personal experience, formed entirely from observing the effects of alcohol. Check out the movie, “Reefer Madness.” The sexual promiscuity, licentiousness, and violence are all characteristic of alcohol, not marijuana.

Pot makes you extra cautious and self-conscious, while alcohol has the OPPOSITE effect!

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