JAN 24, 2019 12:06 PM PST

Can Marijuana Cause Schizophrenia?

WRITTEN BY: Amy Loriaux

We have discussed in this newsletter about how marijuana, in some people, can cause psychosis. This usually occurs with a very potent strain of cannabis (>30% THC). However, it is important to remember that this psychosis is temporary, and can be caused by a number of substances (caffeine, nicotine, alcohol, stimulants, and, obviously, hallucinogens).

Photo source: Pixabay.com

Psychosis is defined by the Diagnostic and Statistical Manual of Mental Disorders (DSM) broadly as a “gross impairment in reality testing” or “loss of ego boundaries” that interferes with the capacity to meet the ordinary demands of life. The Boston Globe defines drug-induced psychosis as "temporary disorientation that resembles a waking dream, with odd, imagined sights and sounds, often accompanied by paranoia or an ominous sensation".

However, while as scary this may be, it is most likely not associated with schizophrenia. Schizophrenia is not a uniform disorder but more of an umbrella term for an array of unexplained problems involving recurrent psychosis and other common symptoms. It is "most likely" because the field is still mixed. For instance, Dr. Margaret Haney, a professor of neurobiology at Columbia University Medical Center has stated: “I’ve been doing this research for 25 years, and it’s polarizing even among academics.”

Schizophrenia is a disease with premorbid symptoms (symptoms that show up before the official diagnosis) such as low affect (emotion), documented changes in brain volume, and is linked to a host of putative genetic mutations. It also is more prevalent in males. Nevertheless, many studies suffer from the "correlation is not causation" effect. Many people who develop schizophrenia (which does not clinically appear until your early 20's) may have smoked marijuana. It is the most widely used illicit substance in the US after all. Yet this still does not mean that marijuana caused schizophrenia.

The field's consensus, as of now, is that marijuana use can exacerbate schizophrenic symptoms and could accelerate the diagnosis of schizophrenia. In other words, people with predictors of developing schizophrenia (family history, premorbid symptomology, being male) have a predisposition for a diagnosis of schizophrenia after smoking cannabis. Most marijuana users start in their late teens and early 20's, so the timing makes it easy to connect the two together.

Photo source: Pixabay.com

Essentially, the theory is that people who are likely to develop schizophrenia will develop it quicker if they use marijuana. An important message to carry away from this theory is the fact that it identifies another subpopulation (in addition to adolescents) that should stay away from pot. The trouble is there is no test that will tell you that you will develop schizophrenia, even if you have it in your family. So you cannot be sure whether the cannabis caused the schizophrenia, or whether you would have developed schizophrenia anyway and the weed merely hastened its arrival (which is still not a good outcome). 

Interesting fact: do you know which drug is most heavily correlated with schizophrenia? Nicotine. About ninety percent of schizophrenic patients smoke cigarettes. But we already know that cigarettes are bad for you, so this does not seem as concerning as to whether cannabis contributes to the disease. Furthermore, these patients may be smoking to ease symptoms, as the cholinergic system in the brain (which nicotine activates) may be involved in the symptoms of schizophrenia. 

The best advice (from your's truly) for folks who are concerned about developing schizophrenia is, if you have a known psychotic disorder or if schizophrenia runs in your family, you may want to rethink smoking that joint. 

SourcesLabRoots.com, BostonGlobe.com, Behavioral Neurology and Neuropsychiatrywww.drugabuse.gov, Rosenberg's Molecular and Genetic Basis of Neurological and Psychiatric Disease (Fifth Edition), New England Journal of Medicine, www.WebMD.comCurrent Psychosis & Therapeutics Reports, European Archives of Psychiatry and Clinical Neuroscience

 

About the Author
  • I currently work at a small CRO involved in clinical trial management.
You May Also Like
MAY 25, 2021
Health & Medicine
Cannabis: Could it Help Chronic Itch?
MAY 25, 2021
Cannabis: Could it Help Chronic Itch?
Chronic itch —clinically known as chronic pruritus — is characterized as an unrelenting sensation to scratch ...
JUN 16, 2021
Health & Medicine
CBD Consumption Linked With Lower Alcohol Intake
JUN 16, 2021
CBD Consumption Linked With Lower Alcohol Intake
Drink and drugs and rock ‘n’ roll may have defined the life of a few in the seventies, but the  fact of ...
JUN 22, 2021
Cannabis Sciences
Report Finds Most First-Time Cannabis Users are Women
JUN 22, 2021
Report Finds Most First-Time Cannabis Users are Women
Chicago-based cannabidiol (CBD) and cannabis-focused market research organization, Brightfield Group, has published a ne ...
JUN 28, 2021
Health & Medicine
Researchers Begin Clinical Trial to Test CBD in Autism
JUN 28, 2021
Researchers Begin Clinical Trial to Test CBD in Autism
Researchers at the University of California at San Diego plan to study whether CBD oil can be of help for children with ...
JUL 27, 2021
Health & Medicine
Marijuana Use Does Not Encourage Extra Cigarette Smoking: Study
JUL 27, 2021
Marijuana Use Does Not Encourage Extra Cigarette Smoking: Study
Recreational marijuana is now legal in 19 states, as well as in Washington, D.C., and Guam. But has this loosening of ca ...
SEP 01, 2021
Health & Medicine
Does Regular Cannabis Affect Brain Function? Sometimes in a Good Way
SEP 01, 2021
Does Regular Cannabis Affect Brain Function? Sometimes in a Good Way
With cannabis now legal in many parts of the world, an increasing number of people now count as regular users of the dru ...
Loading Comments...