Marijuana: heavy users have up to double risk of psychotic episodes

Marijuana: heavy users have up to double risk of psychotic episodes

It is not uncommon to have a family law dispute about children and one of the issues is about one of the parents (sometimes both) smoking marijuana, more often than not being the father. In those types of cases, it is not unusual to read allegations of violence, irrational behaviour and psychotic episodes.

Although much less common, it can be very sad when one of the parties has schizophrenia.

Researchers have long suspected a link between marijuana use and schizophrenia. It is a type of chicken and egg argument- some researchers suggesting that marijuana use may be a cause of schizophrenia, and others saying that it is schizophrenics who use marijuana.

Research just published in the Australian and New Zealand Journal of Psychiatry is truly scary. It says:

-Marijuana has the lowest initiation age of any illicit drug, with users typically starting in early adolescence;
– a little over 1/3 of people aged 14 years and over had used marijuana at some point in their lives;
-17% reported having used it within the last year;
-the association between marijuana and the risk of subsequently
developing schizophrenia is consistent, dose dependent and higher if cannabis is used at an early age;
-there is now evidence demonstrating an association between increased rates of cannabis use and new cases of schizophrenia;
The risk of psychosis is increased by approximately 40% in people who have used cannabis;
The risk of psychosis increases up to double for the most frequent users;
If having ever used marijuana increases risk of a psychotic outcome by up to more than double those of non-users;
approximately 14% of psychotic outcomes in young people would not have occurred if marijuana had not been consumed;
– 25% of schizophrenia patients have a marijuana use disorder, making
it the most commonly used illicit drug among schizophrenics;
-marijuana using patients experience more psychotic symptoms, respond
poorly to neuroleptic medications, have poorer treatment compliance and worse clinical outcomes;
-experience more relapses and more hospitalizations;
– prenatal marijuana exposure affects some neural systems at least into young adulthood. No association has been reported, however, between maternal marijuana smoking during pregnancy and schizophrenia in the offspring;
Prenatal marijuana exposure in laboratory animals resulted in the demasculinization of male animals;
-Prenatal treatment with cannabinoids (the active constituent of marijuana)
resulted in abnormalities in lab animals in motor activity, sociality, stress response and cerebral reward mechanisms. The effects of treatment
were detected only once the animals were in adolescence;
– the onset of abnormalities in lab animals was earlier and worse in male animals, in striking parallel to the gender differences seen in schizophrenia;
– some people are genetically predisposed to mental health issues from marijuana.

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