Legalizing cannabis use is a controversial matter. Both sides of the argument can come with valid compelling points. But there are many aspects of the issue that are not properly researched due to cannabis prohibition. One group claims marijuana can be used as a form of self medication to manage or cope with mental illness. The other believes the herb can be detrimental to mental health and that it could be a fundamental factor in triggering psychosis. And though the studies are not yet decisive, the link between smoking or consuming cannabis and psychosis remains an essential and interesting topic to explore.
What Is a Drug-Induced Psychosis? *
If you have ever tried smoking weed or consuming edibles, or have discussed marijuana use with a friend who had, you’re probably familiar with the drastic change in perspective that comes with the “high.” It is part of the process and it is why most people do it. And while, for the majority of users, the altered state of mind is not very alarming, for others, it can be quite a terrifying experience.
Drug-induced psychosis is a temporary condition where a drug user (cannabis included) experiences a state of mind resembling a psychotic episode. It lasts for a few days and the afflicted may suffer from delusions, hallucinations, high levels of anxiety, paranoia, derealization and depersonalization, and general confusion. Usually, it passes on its own, but it can be so disorienting to require hospitalization. And although the condition is definitely bad news, it can mostly be considered a lengthy bad trip, and thus drug-induced psychosis is not what we are specifically covering in this article.
Can Cannabis Induce a Mental Disorder? *
Many adolescents start experimenting with marijuana early on, and a good number of those may overuse it and carry on with the habit into adulthood. It is suggested that extensive use of strong cannabis in early years may contribute to the development of a psychotic illness (schizophrenia, bipolar disorder, …) or depression. But the link between regular use of cannabis and psychosis is not that straightforward, and there are many factors to keep in mind before one can establish an informed opinion on the existence, or lack thereof, of a cause-and-effect relationship between the two.
The Word “Induce” May Not Be Accurate *
The claim that cannabis alone can induce a psychotic disorder in an otherwise completely healthy individual is not widely accepted; rather, studies have shown that cannabis may trigger an already existent, though dormant, condition. Some people are more genetically predisposed to developing a mental condition. Those, according to research, are most at risk of a marijuana high going disastrously wrong. Nevertheless, because human psychology is very complex, many determinants involved in the process may overlap and result in indefinite outcomes.
Does Cannabis Cause, Trigger, or Merely Coexist with Psychosis? *
Different (and often opposing) hypotheses can possibly explain the link between cannabis and psychosis.
Cannabis as a Contributing Cause *
This hypothesis adopts the claim that cannabis is a contributing factor in the development of psychotic disorders. A study on a sample of more than 45.000 Swedish males, over the course of 15 years, has shown that the risk of developing schizophrenia was 2.4 times higher in individuals using cannabis since youth. The risk was almost tripled to 6 times higher in individuals who used cannabis more than 50 times.
While the previous result (and those of similar studies) may suggest a direct connection between cannabis and psychosis, the study seems to receive a lot of criticism, including the use of self-administered questionnaires and accounting for neither the use of other substances (like alcohol or stronger drugs) nor the personality traits of the participants which may or may not affect their predisposition to cannabis use and/or schizophrenia.
The main argument against this hypothesis is
if cannabis use really does increase the risk of psychosis then shouldn’t there be a corresponding number of diagnoses of psychosis in places where cannabis use is particularly high for example?
And although cannabis may not increase the rate of individuals developing psychosis, it might very well increase the symptoms, worsen the condition, cause more frequent hallucinations and delusions and generally result in more relapses.
Cannabis as a Method for Self-Medication *
This hypothesis suggests that those with a yet undiagnosed psychosis are more likely to take up cannabis use to self-medicate and cope with symptoms. Cannabis is known to induce a sense of calm, and may help the user deal with anxieties or social pressure. So though it might appear that the diagnosis of a mental condition succeeded the cannabis use, and that the latter could thus be causative, the truth is that the psychotic disorder has always been there and might have been the sole motivation for the patient’s cannabis’ habit in the first place.
Cannabis as a Risk Factor to the Vulnerable *
This hypothesis suggests that some people are genetically more prone to developing a psychotic condition than others. Accordingly, cannabis may not be the primary cause of their psychosis, but a risk factor to their already vulnerable mental health.
Mental illness is often explained by the stress diathesis model. This model understands behaviours and illnesses and in this case, psychosis-related illnesses, as being a product of the interaction between a vulnerable hereditary predisposition, with precipitating events or “stressors” in the environment. There are many recent studies which support this hypothesis and essentially see cannabis use as a factor or stressor that may interact with an underlying susceptibility.
Finally, it is safe to say that the scientific community has not yet found the ultimate answer to our main question. But enough studies have shown a relationship between regular use of cannabis and psychosis, so it is generally advisable to steer clear from that joint if you have a family history of a mental condition. And if you frequently encounter extreme psychedelic highs, or are using cannabis to relieve consistent feelings of melancholy or anxiety, please make sure to speak with your doctor and find the underlying problem. Better safe than sorry!
For a more extensive account of the studies involved in the previous hypotheses, read here! And for a list of arguments and refutations for and against the link between cannabis and psychosis, read here!