What Are Examples Of Psychosis Causes?

Reviewed by Aaron Horn, LMFT

Published 06/27/2022

Psychosis can have many causes, and contrary to popular belief, it’s referring to a set of symptoms - hallucinations and delusions, and it’s not a specific mental health disorder. This article will learn about some of the potential causes of psychosis and what can be done to treat the symptoms.

Various Mental Health Disorders

As mentioned in the introduction, psychosis isn’t a condition; rather, it’s a sign of a much larger issue.

Several mental health disorders can cause psychotic symptoms, and schizophrenia is the most well-known one. So, what are the first signs of schizophrenia?

When people think of schizophrenia, psychotic symptoms are typically what comes to mind, such as hallucinations and delusional beliefs; however, these can be seen in many other disorders.

Bipolar disorder is another well-known condition, but many people don’t know that psychosis can occur, especially during manic episodes. It can also occur during depressive episodes. Even people who struggle with unipolar depression, or just simply major or clinical depression, may run into what is known as psychotic depression.

Related to these, schizoaffective disorder is a condition that combines features of schizophrenia with mood disorders like bipolar disorder and major depression. However, unlike schizophrenia, psychosis in schizoaffective disorder can come and go and isn’t as chronic as schizophrenia. Still, it should always be taken seriously, even though it can be temporary.

People with Alzheimer’s disease and other neurodegenerative diseases that cause dementia can also display psychotic symptoms.

Since psychosis is a common denominator for many disorders, mental health professionals must look at the other symptoms, such as mood changes, to determine the most accurate diagnosis.

Therefore, psychosis symptoms are just one piece of a puzzle, and everything should be taken to account.

Substance Abuse

The next most common cause of psychosis is substance abuse, and people who consume certain types of drugs may be more prone to have a psychotic break.

Stimulants, such as amphetamines and methamphetamines, which are legal and illegal, respectively, are examples of drugs that can cause what is known as amphetamine-induced psychosis.

These drugs are frequently used among patients who have psychiatric troubles, and the signs and symptoms are very similar to those who have schizophrenia but don’t abuse amphetamines. [1]

Nonetheless, these issues often go hand-in-hand, but there people who abuse these drugs and don’t have a severe mental illness like schizophrenia yet experience psychotic symptoms.

Psychosis is also associated with alcohol use, whether it’s from acute intoxication or withdrawal. It is particularly common in individuals with chronic alcohol use disorder, and the effects often appear during or shortly after heavy drinking. [2]

The most common psychotic symptoms associated with alcohol-related psychosis are hallucinations, paranoia, and fear, but delusions can also be present.

The primary mechanism that is believed to be responsible for psychosis due to substance use and abuse is the brain's dopaminergic activity.

Alcohol and stimulants are known to cause an increase in dopamine levels, which can cause psychosis. Similarly, schizophrenia is also correlated with having excess dopamine levels.

Antipsychotic medication aims to balance dopamine levels in the brain, and by doing so, people can find relief for their symptoms.

Sleep Deprivation

Another possible cause of psychosis for people is a severe lack of sleep.

Thinking abnormalities can appear as soon as 24-hours without sleep, but it gets progressively more severe the longer someone stays awake. Studies show that, on average, after 48 hours of no sleep, people can start to hallucinate, and delusions often appear after 72 hours. [3]

Staying awake for 24 hours is difficult and unhealthy, but it isn’t out of the ordinary for people who are in college or work third shift jobs. Examples include pulling an all-nighter studying or staying awake to drive through the night. However, staying awake for extreme periods of time is often due to substance use - especially stimulants, as mentioned in the previous section.

While there is a strong connection between substance abuse and sleep deprivation, it’s not always the cause of it.

People can also struggle with insomnia, especially those who have underlying conditions like depression and anxiety. While they don’t necessarily need to stay up for 24 hours or more in a single day, they are more likely to develop sleep debt.

If an individual who has sleeping issues regularly only gets a few hours of sleep most nights, rather than the recommended 7 to 9 hours, they may experience a deficit of sleep hours, which can keep growing and possibly cause the first signs of psychosis are. [4]

People who have a bad night of sleep can often catch up the next day, but those who have chronic issues getting enough sleep might never catch up.

This means that the brain isn’t able to recover as needed, leading to psychiatric concerns.

Infectious Disease

One cause of psychosis that often gets overlooked is infectious diseases. There are several that can create symptoms.

Here are some examples of diseases that have been documented to cause psychosis: [5]

  • Lyme Disease
  • Malaria
  • Syphilis
  • HSV-1 and 2 (Herpes simplex)
  • Eastern equine encephalitis
  • Borna disease
  • Influenza
  • Measles
  • Polio
  • Vaccinia
  • Rubella
  • Epstein-Barr
  • Toxoplasmosis

Infectious diseases can be caused by a wide array of hosts - there are viruses, bacteria, parasites that can also contribute to the onset of these diseases. They can also be transmitted through different means, such as by sexual contact, by a vector (like mosquitoes and ticks), poorly cooked food or contaminated water, and through the air.

Because of the connection between infectious diseases and psychosis, it was once hypothesized that schizophrenia is caused by them. Still, modern imagery and autopsies have mostly ruled out encephalitis (inflammation of the brain) as a cause for the disorder. [5]

However, encephalitis and meningitis (inflammation of the brain lining and spinal cord) caused by microbial infections, such as those that lead to the diseases listed above, can create psychosis. Therefore, treating the infection can help people with these symptoms.

Therefore, according to the CDC, vaccines and antimicrobial agents may be a viable option for people with mental illnesses. If even only 1 percent of people had psychiatric symptoms due to an infection, it could equate to around 10 million people benefiting from antimicrobial therapy. [6]

Brain Tumors

Lastly, another medical concern is brain tumors. These abnormal cell-masses can cause many issues by affecting the brain tissue, and psychosis is one of them.

Some brain tumors are benign, and others are malignant. Malignant tumors are cancerous, and they didn’t originate in the brain a lot of the time. These are called secondary brain tumors, and they often start from lung, skin, breast, and kidney cancers and spread to the brain, creating common symptoms such as [7]

  • Headaches
  • Vision problems
  • Seizures
  • Memory loss
  • Confusion
  • Motor issues

Of course, a person’s perceptions and senses, decision-making, mood, and personality can be affected. Depending on where a tumor is located, it can cause people to hallucinate based on different senses.

For example, if it’s in the brain area that is responsible for vision, they might see the light or other things that aren’t there, whereas others might affect hearing, taste, touch, and smell.

Some brain tumors can be treated with surgery, radiation therapy, and chemotherapy. People can recover and notice significant improvements in different functions that may have been compromised by the tumor and find relief for mental issues, like psychosis.

Does Your Loved One Have Psychosis?

As you can see, psychosis can be due to many different things, and those who are experiencing it often don’t realize that their thinking is disordered and disconnected from reality.

Helping people with psychosis often requires an intervention from people close to them who start to notice that things are unusual with their loved one. They can be the first step towards getting a referral to a professional.

A doctor or mental health professional can help explain why someone is having psychotic symptoms and give them an assessment and diagnosis. Their exam might involve medical testing for infectious diseases and brain abnormalities. Afterward, they could be prescribed medication, such as antipsychotics, to help people cope with the symptoms.

If you aren’t sure if you’re loved one is experiencing is psychosis, you can take this free psychosis test to try to find out.

Ultimately, a diagnosis will be required from a professional, but recognizing the signs and symptoms is crucial in helping people get the assistance they need.


Psychosis is much more than schizophrenia. Hopefully, this article has shed some light and created awareness about what can trigger a psychotic episode and the early warning signs of psychosis. Luckily, psychosis isn’t always permanent, and it can be managed effectively through medication and other resources, and people can go back to living healthy and productive lives.


  1. Bramness, J. G., Gundersen, Ø. H., Guterstam, J., Rognli, E. B., Konstenius, M., Løberg, E. M., Medhus, S., Tanum, L., & Franck, J. (2012). Amphetamine-induced psychosis--a separate diagnostic entity or primary psychosis triggered in the vulnerable?. BMC psychiatry, 12, 221. https://doi.org/10.1186/1471-244X-12-221
  2. Stankewicz HA, Richards JR, Salen P. Alcohol-Related Psychosis. [Updated 2020 Jul 17]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2020 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK459134/
  3. Waters, F., Chiu, V., Atkinson, A., & Blom, J. D. (2018). Severe Sleep Deprivation Causes Hallucinations and a Gradual Progression Toward Psychosis With Increasing Time Awake. Frontiers in psychiatry, 9, 303. https://doi.org/10.3389/fpsyt.2018.00303
  4. Gotter, A. (2019, November 13). Sleep Debt: What It Means for Your Health and How You Can Pay It Off. Retrieved from https://www.healthline.com/health/dr/sleep-deprivation/sleep-debt
  5. Yolken, R., Torrey, E. Are some cases of psychosis caused by microbial agents? A review of the evidence. Mol Psychiatry 13, 470–479 (2008). https://doi.org/10.1038/mp.2008.5
  6. Mcsweegan, E. (1998). Infectious Diseases and Mental Illness: Is There a Link. Emerging Infectious Diseases, 4(1), 123-124. doi:10.3201/eid0401.980118
  7. Han, S. (2017, June 6). Brain Tumor. Retrieved from https://www.healthline.com/health/brain-tumor