SOD Chapter 3.3 - Subchapter 1 - schizophrenia.life

3.3.1. CANNABIS USE AND SCHIZOPHRENIA

Cannabis use is surprisingly common among individuals with psychosis.

Studies show that nearly 36% of people experiencing their first episode of psychosis, and about 21% of those with established schizophrenia, struggle with cannabis use disorders (CUD).

Can cannabis use increase the risk of schizophrenia?

Cannabis use, especially in large amounts, significantly raises the likelihood of developing schizophrenia, with the risk being particularly high in those who start using it at a younger age. Studies suggest that people who frequently use cannabis are up to four times more likely to experience schizophrenia.

Additionally, the severity of risk depends on:

Age of first cannabis use (higher risk if use begins before age 16-18).
Dose and potency (heavier use and high-THC cannabis increases risk).
Genetic vulnerability (family history of psychosis plays a role).

Cannabis-induced psychosis: a growing concern

The number of cannabis-induced psychosis cases has dramatically increased over the past two decades:

From 2000 to 2016, cases of “cannabis-induced psychosis” jumped by 67% in Norway, 115% in Denmark, and 238% in Sweden.
In Canada, emergency room visits for cannabis-related psychosis doubled between 2015 and 2019.

This is a serious concern, as many of these individuals go on to develop lasting psychotic disorders.

Why do people with schizophrenia use cannabis?

Self-medication: Some patients use cannabis to alleviate distressing psychotic symptoms or counteract the unpleasant side effects of some medications.

Managing negative symptoms: Some believe that cannabis might help improve negative symptoms of schizophrenia, such as social withdrawal, lack of motivation, and emotional flatness.

From 2000 to 2016, cases of “cannabis-induced psychosis” jumped by 67% in Norway, 115% in Denmark, and 238% in Sweden.
In Canada, emergency room visits for cannabis-related psychosis doubled between 2015 and 2019.

Coping with anxiety and stress: Studies show that schizophrenia patients are more likely to use cannabis during stressful events, even though it can increase psychotic symptoms.

While some patients turn to cannabis for relief, its use can complicate treatment, exacerbate symptoms, and interfere with medications.

Understanding the reasons behind cannabis use and its potential risks is crucial for caregivers to provide effective support and ensure the best outcomes for their loved ones.

Cannabis use and schizophrenia: what every caregiver should know

Recent research highlights the significant connection between cannabis use and schizophrenia.
Cannabis use has been consistently linked to an increased risk of developing psychosis and worsening schizophrenia symptoms.
Studies show that reducing or eliminating cannabis intake can help prevent or even improve the symptoms of schizophrenia.

While other risk factors, like drug use, urban living, or social class, may also play a role, cannabis remains a clear risk factor.

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