What Drugs Cause Psychosis?
Several drugs can cause psychosis, including substances that are sold legally and others that are not.
Drugs known to cause psychosis include the following:[2]
- Cannabis: Cannabis can cause psychotic symptoms that can last from a few days to a few months, depending on the amount of THC in each dose.
- Synthetic cannabis: Drugs like Spice and K2 work much like THC, and they can also cause short-lived psychosis.
- Cathinone derivatives: Drugs like mephedrone can cause mild agitation or severe psychosis that lasts for short periods.
- Cocaine: Cocaine works on several key areas of the brain, blocking neurotransmitters and reducing cell communication. Psychosis is relatively common while people are intoxicated with cocaine, but it doesn’t last long.
- Methamphetamine: Meth causes brain cells to release dopamine and glutamate, which can damage the brain’s communication pathways. People who use meth are often at a higher risk of psychosis, and it can last after the drug wears off.
- Hallucinogens: Drugs like psilocybin, LSD, and mescaline can sometimes cause psychosis as they latch to receptors in the brain that interpret visual and auditory information. Symptoms can last for hours.
- Entactogens: Drugs like MDMA increase key brain chemicals like dopamine, norepinephrine, and serotonin. MDMA can cause psychosis, but it’s rare. People who have it can experience symptoms for several days.
- Ketamine and PCP: These two drugs increase dopamine and glutamate levels in the prefrontal cortex of the brain. Some people develop temporary psychosis while using these drugs.
Alcohol can also cause a unique form of psychosis when long-term drinkers try to quit or cut back. Alcohol works by interacting with GABA receptors in the brain, slowing overall activity. When heavy drinkers quit and the brain wakes up, cells overreact and people develop symptoms including psychosis. The condition is known as delirium tremens, and it can last for several days.[6]
What Does Drug-Induced Psychosis Look Like?
Psychosis involves two symptoms: delusions (false beliefs) and hallucinations (sensing things others do not). Inappropriate behavior or speech is common as people try to make sense of their experience.[1]
Someone experiencing a drug-induced psychotic episode may show the following signs:[1]
- Suggesting that people are attempting to harm them
- Believing that objects like televisions or phones are sending secret messages
- Muttering about these unusual beliefs
- Pacing, clenching fists, and placing hands over ears
- Speaking incoherently
- Doing things (like removing clothes or yelling) in spaces where this isn’t normal
It can be hard to separate a drug-triggered psychotic episode from one sparked by mental illness. Experts say the term drug-induced psychosis only applies in situations where the person has symptoms during times of intoxication or withdrawal.[3] If someone with no drug history experiences psychosis, another cause is to blame.
How Many People Experience Drug Psychosis?
The National Alliance on Mental Illness says about 100,000 people experience psychosis every year, and as many as three in 100 people will have an episode at some point in their lifespan.[7] For some people, these episodes either start or are worsened by drug use.
The American Psychiatric Association says between 7% and 25% of people experiencing their first psychotic episode have a substance/medication-induced psychotic disorder.[8] In other words, their symptoms can be tied almost exclusively to their drug use.
The Substance Abuse and Mental Health Services Administration says determining the prevalence of psychosis caused by drugs vs. psychosis caused by mental illness isn’t easy. Many studies report rates for both without separating them. Some studies report current use, while others discuss lifetime use. The people included in studies can vary too.[9]
While it’s hard to know exactly how many people experience drug psychosis, it’s clear that far too many users struggle with this issue after using substances.
Risk Factors for Drug Psychosis
Taking drugs is the largest risk factor for drug psychosis. People who stay sober don’t experience these episodes, as they don’t change brain chemistry with substances.
Researchers say psychosis is more common in people with the following triggers:[4]
- Stress
- Traumatic brain injuries
- Genetic predisposition
Researchers don’t fully understand the link between mental health issues (like schizophrenia) and drug psychosis. Studies suggest that people who experience a psychotic episode while on drugs are more likely to develop mental health issues like bipolar disorder and schizophrenia.[3] However, it’s not clear if the drug used caused these mental health concerns or if a shared vulnerability exists between developing drug psychosis and mental health disorders.
How Is Drug Psychosis Treated?
Drug psychosis symptoms are often brief, and they fade when the body processes all active ingredients and allows brain chemistry levels to return to neutral. Exceptions exist, however. Substances like cocaine and amphetamines can cause psychosis lasting weeks.[2]
It’s critical to get help for anyone experiencing drug psychosis. Doctors can use medications like benzodiazepines and antipsychotics to keep symptoms under control and help the person return to a healthy state.[2] Doctors can also help people understand their risk for future problems, which could prompt them to enter treatment programs for addiction.
Can You Prevent Drug Psychosis?
The best way to reduce drug psychosis is to enter a treatment program and stop substance abuse. Researchers say people who have taken high doses of drugs for long periods are more likely to develop psychosis than short-term, recreational users.[3]
For example, researchers say marijuana psychosis is closely associated with higher doses. Heavy users have a four-fold risk of developing symptoms compared to those who don’t use the drug.[5]
People with a long history of drug use may need treatment to help them quit. If they attempt to stop drug use without help, they may be more likely to relapse and experience another difficult psychosis episode.
Addressing Addictions & Mental Health Disorders
The National Alliance on Mental Illness says the use of drugs like marijuana, LSD, and amphetamines can increase the risk of psychosis in people who are already vulnerable due to these episodes.[7]
A comprehensive treatment program won’t prioritize one issue over another. People aren’t forced to choose between dealing with an addiction or a mental health issue first while allowing the other condition to get worse. Instead, providers help people to address both problems simultaneously.
A program like this can include medication management, counseling, support groups, education, and more. Inpatient settings allow people to move into a facility (and away from triggers) to focus on healing. Others are offered on an outpatient basis, so people can keep living at home while they get better.
How to Help Someone Experiencing Psychosis
Someone experiencing a psychotic episode needs your help. A person like this may not be able to recognize the difference between a hallucination and reality, and problems can escalate very quickly. You can help keep the person, and your community, safer.
Take these steps to help someone experiencing psychosis:[6]
- Use a calming tone. Keep your voice quiet, low, and gentle. Don’t yell or scream at the person.
- Listen actively. Ask the person to explain what’s happening. Express sympathy and understanding.
- Express your concern. Repeat what the person has told you about the experience. Explain that you’d be worried about those thoughts and feelings too. Don’t attempt to reason their experience away.
- Give real help. Offer to sit with the person, drive them home, or otherwise provide practical assistance. Don’t leave them alone.
Some people experiencing drug psychosis need help in a hospital. If the person is in danger of harming themselves or someone else, they need urgent care from medical professionals.
If you can calm the person down and wait out the intoxication, your work isn’t done. Psychotic symptoms could reappear if the person uses drugs again. Talk to the person about the benefits of treatment and offer to help them get the help they need.
Learn More About Psychosis & Mental Health
Understanding psychosis and mental illness can ensure you’re a helpful ally when something goes wrong. The following resources may help:
- The National Institute on Drug Abuse’s page Understanding Drug Use and Addiction can help you understand why substances are hard to quit.[7]
- The National Alliance on Mental Illness’s page Schizophrenia can help you understand this mental illness and how it might be different from drug-induced psychosis.[8]
- The National Alliance on Mental Illness also has a podcast on Psychosis that can provide deeper insight.[8]
Prevent Drug Psychosis
The best way to block future drug psychosis episodes is to quit using drugs.[9] Doing so isn’t always easy. If someone you love is struggling with drugs, talk about the benefits of treatment and offer to help them get started. You could be just the source of help that person needs.
- Psychosis. National Alliance on Mental Illness. Accessed January 26, 2024.
- Substance-induced psychoses: An updated literature review. Fiorentini, A., Cantu, F., Crisanti, C., Cereda, G., Oldani, L., and Brambilla, P. Frontiers in Psychiatry. 2021; 12.
- Drug abuse and psychosis: New insights into drug-induced psychosis. Ham, S., Kim, T., Chung, S., and Im, H. Experimental Neurobiology. 2017;26(1):11-24.
- Substance-/medication-induced psychotic disorder. Tamminga, C. Merck Manual Professional Version. Published April 2022. Accessed January 26, 2024.
- Medications, counseling, and related conditions. Substance Abuse and Mental Health Services Administration. Published September 28, 2023. Accessed January 27, 2024.
- Delirium tremens. Rahman A, Paul M. StatPearls. Published August 2023. Accessed April 19, 2024.
- Psychosis. National Alliance on Mental Illness. Accessed April 19, 2024.
- Substance-induced psychosis in first episode programming. Hendrick D, Drake R. Substance Abuse and Mental Health Services Administration. Accessed April 19, 2024.
- First-episode psychosis and co-occurring substance use disorders. Substance Abuse and Mental Health Services Administration. Published 2019. Accessed April 19, 2024.