Cannabis is the most widely used illegal drug in the UK. Many people consider it safe to use, but there has also been a lot of concern about the substance’s potential effects on mental health, including serious conditions such as psychosis.
So, how common is cannabis-induced psychosis? We’ll put aside any alarmist claims and take a look at the facts…
Cannabis Use and Mental Health Concerns
Cannabis use actually fell in the latest set of official figures, but use of the drug is still widespread. An estimated 6.8% of people aged 16 to 59 years reported using cannabis in the previous 12 months in England and Wales. That represented around 2.5 million people in those two countries alone.
According to the Royal College of Psychiatrists, there is now plenty of research establishing a link between various mental health conditions, including depression, suicidal thoughts and anxiety. Research suggests those already at risk of developing mental health issues could be at an increased risk of showing symptoms if they use cannabis regularly. Cannabis can also make these problems worse.
Some research has also shown a link between using cannabis and an increased risk of psychosis.
What is cannabis-induced psychosis?
Psychosis is a serious mental health condition that involves people losing some contact with reality.
The three main symptoms are:
- Hallucinations: where the person experiences things that are not there, such as hearing voices in their heads.
- Delusions: where the person has strong beliefs that are not experienced by others, such as believing there is a conspiracy to harm them.
- Disordered thinking: thoughts are jumbled, and their speech can be fast and confusing.
Psychosis can be related to mental health conditions, including schizophrenia, bipolar disorder and severe depression.
Cannabis-induced psychosis refers to a case of psychosis that has been triggered or exacerbated by cannabis use. This may involve short-term psychotic episodes but there may also be a long-term risk of schizophrenia-like conditions.
How Common is Cannabis-induced Psychosis?
It isn’t easy to get exact figures but a number of studies have looked at the prevalence of cannabis-induced psychosis. One study found that less than half a percent of individuals using cannabis report related psychosis that requires emergency medical treatment, with paranoia being the most prevalent feature. It’s worth noting that half a percent of the 2.5 million users noted above would still be more than 12,000 people.
This figure may also be on the rise thanks to heavier use and stronger strains of cannabis. Two Canadian studies found a 220% increase in emergency room visits in Ontario for cannabis-induced psychosis between 2014 and 2021, representing an increase from around 400 to 1,400 people.
A wider review of numerous studies found that between 2% and 21% of users experienced some psychotic symptoms after consuming cannabis – although the lowest rates were observed in studies assessing medicinal cannabis and the highest in experimental studies administering the psychoactive ingredient THC.
The widely different results show that is difficult to estimate the precise risks of cannabis-induced psychosis, but that those risks can certainly exist. They can also vary for some groups, including younger users and heavier users of the drug.
Risk Factors for Cannabis-induced Psychosis
Some risk factors for cannabis-induced psychosis include frequency of use and the potency of cannabis involved. Over a period of years, strains of cannabis have been bred to be stronger, in particular with greater proportions of THC.
The age of the user and the age at which they first started using cannabis can also have an effect. Younger users who start in adolescence can be at greater risk of developing psychosis and other mental health conditions.
Some people may also have a genetic predisposition, making them more vulnerable to mental health issues, including psychosis. In such cases, psychosis may develop anyway, but cannabis use could trigger symptoms or make them worse than they would otherwise be.
Short-term vs Long-term Outcomes
Short-term or acute psychotic episodes may resolve themselves after use of the drug, or some time after the user quits using the drug. However, continuing cannabis use can also lead to a higher risk of developing chronic, long-lasting psychotic disorders.
An online global survey found that more than half (56%) of respondents who experienced cannabis-associated psychosis reported that it resolved within 24 hours. However, a fifth said that symptoms lasted for at least several weeks. People who develop serious mental health conditions like schizophrenia may need ongoing treatment.
It’s important to note that not everyone who uses cannabis will develop psychosis or psychotic symptoms, but the risks can be significant.
The Impact on Young People and Communities
A study specifically looking at age, cannabis use and psychotic disorders estimates that teens using cannabis are at 11 times higher risk of developing a psychotic disorder than those who don’t.
Cannabis use can also have wider societal costs, adding extra burden to an already under-pressure NHS and mental health services.
When to Seek Help for Cannabis-induced Psychosis
If you believe you or someone you know is experiencing cannabis-induced psychosis, you should seek medical help immediately. You should see your GP if there are ongoing signs of psychosis, but for an acute episode, which can often arise with cannabis-induced psychosis, you can call NHS 111 for advice, or call 999 or go to A&E if it is an emergency.
Treatment and Recovery at Cassiobury Court
While some people believe that cannabis is not addictive, it can cause psychological dependence. Cassiobury Court provides cannabis rehab treatment to help problem users regain control of their lives and mental health. Cannabis detox can help you to safely work through the psychological withdrawal symptoms of cannabis, while a range of therapies and relapse prevention sessions can help you to maintain your recovery moving forward.
Awareness and support save lives
It’s important to be aware of the risks and to get help early when problems arise. If you’re worried about cannabis use or its effects on mental health, contact Cassiobury Court for immediate, confidential support.
