Cannabis products are a thriving business, but are you unknowingly increasing your chances of developing schizophrenia?

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“Cannabis and schizophrenia” sounds like a catch-phrase intended to incite fear in those using different cannabis products, like CBD and medical or recreational cannabis.

While cannabis has endured much political and scientific scrutiny throughout the years, it isn’t without its negatives like most natural and manufactured substances.

Not everyone who uses cannabis will develop schizophrenia, but for a small portion of the population, that possibility may be very real.

Cannabis vs. marijuana

You may use the word “cannabis” interchangeably with the word “marijuana,” but there is a slight difference between these two terms.

Cannabis can describe any product derived from the plant Cannabis sativa.

Marijuana is cannabis — but marijuana specifically refers to products from the parts of the cannabis plant containing significant amounts of delta-9-tetrahydrocannabinol (THC).

THC is just 1 of more than 500 chemicals found in the cannabis plant, but its psychoactive effects are why many people turn to cannabis for recreation.

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Is CBD legal? The 2018 Farm Bill removed hemp from the legal definition of marijuana in the Controlled Substances Act. This made some hemp-derived CBD products with less than 0.3 percent THC federally legal. However, CBD products containing more than 0.3 percent THC still fall under the legal definition of marijuana, making them federally illegal but legal under some state laws. Be sure to check state laws, especially when traveling. Also, keep in mind that the FDA has not approved nonprescription CBD products, and some products may be inaccurately labeled.

Schizophrenia is a mental health disorder that involves lapses in your reality, known as psychotic symptoms or psychosis.

A systematic 2020 review looked at 96 studies on cannabis and schizophrenia. After putting the articles through quality assessment, only 12 were found to be high enough quality for inclusion in the review.

From those studies, researchers found:

  • There may be a high frequency of psychotic disorders among people using cannabis.
  • Cannabis use can alter the typical age and onset of schizophrenia symptoms.
  • Cannabis-induced psychosis can eventually convert to clinical schizophrenia.
  • Individuals living with psychotic disorders have a higher tendency to use cannabis.
  • Living with psychotic disorders may increase sensitivity to the psychoactive effects of THC.
  • Frequent use of cannabis, particularly at a young age, can double the chances of developing schizophrenia.
  • Daily use of high-potency THC may result in a 5 times higher chance of developing a psychotic illness.
  • Cannabis use may interact with preexisting factors, like genetics, to increase schizophrenia risk.

Schizophrenia vs. psychotic disorder

Schizophrenia is called a psychotic disorder because it involves symptoms of psychosis, like:

While schizophrenia is often considered the flagship disorder when it comes to psychosis, it’s not the only clinical diagnosis that involves these types of symptoms.

Examples of other psychotic disorders include:

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Cannabis doesn’t cause schizophrenia.

But if you’re already predisposed to schizophrenia through genetics and environmental factors, cannabis use may increase your chances of developing schizophrenia.

This may be, in part, from a naturally occurring sensitivity you might have toward the psychoactive effects of THC.

Drug-induced psychosis vs. drug-induced schizophrenia?

In the Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-5), drug-induced psychotic disorder involves symptoms of psychosis directly linked to a period of substance use, often improving when the substance is eliminated from the body.

Drug-induced schizophrenia is underlying schizophrenia brought to the surface through the use of a substance, like cannabis, but it’s not yet noted in the DSM.

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Symptoms of psychosis have to do with a disconnect from reality.

For example, you may see, hear, smell, taste, or touch things that aren’t there. Your thoughts may not make sense, or you may experience untrue beliefs known as delusions.

For cannabis users, these experiences may sound harmless and familiar.

Higher doses of THC, a psychoactive compound in cannabis, are known for affecting regions of the brain related to sensory and time perception.

It’s not uncommon for people using cannabis to experience symptoms of psychosis seen in schizophrenia, including:

  • Hallucinations: characterized by false sensory experiences.
  • Delusions: thoughts and beliefs that are untrue or don’t match reality.
  • Disorganized thinking: nonsensical thought and speech patterns ranging from subtle to difficult to understand.
  • Negative symptoms: a reduction in certain function areas, such as cognitive decline.

Cannabis use may also cause a feeling of dissociation or a loss of your sense of personal identity.

When do symptoms of psychosis become schizophrenia?

Schizophrenia is a lifelong condition and won’t resolve once cannabis leaves your system.

According to the DSM-5, schizophrenia can be diagnosed when you’ve experienced at least two classic symptoms of psychosis for the majority of time during a 1-month period, with symptoms persisting for at least 6 months.

During this time, symptoms must significantly impair your daily life and functioning, and no current substance use can explain what you’re experiencing.

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Yes, cannabis can trigger acute psychosis without it progressing to schizophrenia.

Psychosis describes episodes of reality disconnect. The causes for these symptoms can be many and complex and may not have to do with schizophrenia.

Not all cannabis use leads to psychosis. These experiences are typically related to high dose THC exposure.

In a 2021 study of more than 109,000 people in the United Kingdom, researchers found that there may be a high association between cannabis dose and the chances of experiencing one of four types of psychotic symptoms, including:

  • auditory hallucinations
  • visual hallucinations
  • persecutory delusions
  • delusions of reference

Not all cannabis products involve THC.

Cannabidiol (CBD) is another compound found in the cannabis plant that may have some therapeutic effects on schizophrenia. Unlike THC, CBD doesn’t typically have psychoactive properties.

CBD may counteract the effects of THC, and some 2018 research suggests it may help to alleviate psychotic symptoms in schizophrenia as effectively as certain prescription medications — and with fewer side effects.

Other 2017 research, however, notes that CBD may increase experiences of hallucinations and negative symptoms in some people, even though it may improve other features of psychosis.

While many ongoing studies are still investigating the uses of cannabis products, like CBD in therapeutic approaches to schizophrenia, these products are not yet considered mainstream.

Can you use cannabis to alleviate schizophrenia symptoms?

Data from a 2020 review indicates that people living with psychotic disorders may be more likely than others to turn to cannabis use.

Researchers speculate that living with a psychotic disorder could make the effects of cannabis more pleasurable.

So while you might think you feel better when you’re using a cannabis product, this doesn’t necessarily mean this substance is treating your schizophrenia or any other psychotic disorder.

A 2021 systematic review trials found no changes in schizophrenia symptoms and cognition for people using smoked or oral THC. The same review also found CBD results to be inconclusive.

The cannabis industry is growing, and with it may be the interest of people who have never tried cannabis products before.

Cannabis isn’t the same as marijuana, though marijuana is a cannabis product.

While links between cannabis and schizophrenia have been identified, using cannabis products doesn’t “cause” schizophrenia.

If you develop schizophrenia after cannabis use, it’s likely because you live with an underlying predisposition for the disorder.

Genetics, your environment, and other physiological elements may interact with cannabis use, resulting in the development of a psychotic disorder.

Symptoms of psychosis can be alarming. You may experience hallucinations or delusions that can compromise your safety.

If you or someone you know is experiencing psychosis, calling your local first responder teams can help ensure they recover in a safe and secure environment.

In both the United States and Canada, you can reach immediate emergency services by dialing 911.