Paranoid Schizophrenia – What is it?

Naomi Carr
Author: Naomi Carr Medical Reviewer: Dr. Jenni Jacobsen, PhD Last updated:

Schizophrenia was previously listed as five subtypes: paranoid, disorganized, catatonic, residual, and undifferentiated [1]. Because of uncertainty around the stability and validity of these subtypes, the most recent publication of the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders (DSM-5) [2], no longer lists these five subtypes [3].

Therefore, paranoid schizophrenia is not given as a diagnosis, but the symptoms of each type of schizophrenia can still be used to inform diagnosis, depending on the severity of each presenting symptom.

What is paranoid schizophrenia?

Schizophrenia often presents with a combination of symptoms, such as:

  • Positive symptoms: including delusions, hallucinations, and thought disorders.
  • Negative symptoms: including catatonia, loss of motivation, social withdrawal, and blunted emotions.
  • Cognitive symptoms: including abnormal or disorganized speech and behavior, such as trouble with following one train of thought, incoherent sentences, and bizarre or repetitive movements.

According to the DSM-IV [1], for a diagnosis of paranoid schizophrenia, one or more delusions and/or hallucinations must be present, with the individual being very focused on at least one specific delusion, which will typically be persecutory in nature, causing a belief that someone or something will do them harm.

The DSM-IV further states that there must be no persistent negative symptoms, or disorganized speech and behavior for a diagnosis of paranoid schizophrenia. Therefore, paranoid schizophrenia presents solely with positive symptoms.

Symptoms of paranoid schizophrenia

Symptoms of paranoid schizophrenia involve one or more hallucinations and/or delusions.

Although visual and auditory hallucinations are most common, schizophrenia hallucinations can involve any of the five senses [4]:

  • Visual hallucinations: seeing things that are not there, such as people, lights, and shapes
  • Auditory hallucinations: hearing things, such as voices talking to you or about you, or an ongoing commentary of your actions
  • Olfactory hallucinations: smelling things that are not there
  • Tactile hallucinations: feeling things that are not there, such as bugs on your skin or someone touching you
  • Gustatory hallucinations: tasting things that are not there

Delusions are strongly held beliefs that are not based in logic, evidence, or reality. Examples of a delusion could include [4]:

  • Perception: an abnormal meaning is assigned to something ordinary. For example, a bird lands in a nearby tree and this is presumed to mean that a plane is going to crash into the White House.
  • Thoughts: thought broadcast, insertion, or withdrawal, causing the individual to feel that they are not controlling their own thoughts. For example, believing that someone can listen to your thoughts, plant thoughts into your mind, or remove them.
  • Idea: a belief, such as thinking that hackers are watching you through your computer camera, or that there is someone following you.

Often with paranoid schizophrenia, these hallucinations and delusions will be persecutory in nature, meaning that the person will believe someone, or something, is trying to harm them in some way. Because of this consistent fear of persecution, symptoms of paranoid schizophrenia can also include [5][6]:

  • Social withdrawal
  • Inability to trust others or form friendships
  • Anger, hostility, or aggression
  • Hearing voices telling you to harm others
  • Hearing voices that make derogatory or nasty remarks about you
  • Believing that people are trying to poison you, that people are following you, or that your home or phone are being watched or listened to
  • Difficulty concentrating or focusing
  • Using illicit substances
  • Suicidal thoughts
  • Treatment noncompliance, such as forgetting or choosing not to take medication, or declining to attend appointments with professionals
  • Poor level of self-care

Causes of paranoid schizophrenia

It is not clear exactly what causes schizophrenia, but there are many theories and fields of research that indicate several factors are involved with the development of the condition.

Brain structure and function

There is research to indicate that an abnormal level of certain neurotransmitters, such as dopamine and glutamate, can cause schizophrenia [7].

Some studies also show that individuals with schizophrenia are likely to have altered brain structures, such as a decreased volume of gray matter, which may suggest that impaired brain development could cause schizophrenia [8].

Similarly, there are several cases in which a traumatic brain injury has triggered an episode of psychosis or schizophrenia, further implying that altered brain structure can increase the risk of developing the condition [9].


Schizophrenia occurs around six times more often in individuals with a parent or close relative with the condition, than in those without, suggesting a strong genetic factor. However, some people with a family history of schizophrenia do not develop the condition, so genetics are not the only contributing factor [7].

Social and environmental influences

The risk of schizophrenia and psychosis may be increased by certain social or environmental factors, such as stress, childhood trauma and abuse, socioeconomic class, social isolation, and complications during pregnancy and childbirth [10][11].

Alcohol and drugs

There is a great deal of research that suggests the use of substances can increase the risk and severity of psychosis with schizophrenia. Cannabis use in particular has been shown to increase this risk, especially in those who regularly use large amounts of cannabis and have done so from a young age [11][12].

Additionally, studies indicate that other substances, such as alcohol, cocaine, and amphetamines, also increase the risk of psychosis [11].

Treatment of paranoid schizophrenia


Typically, all types of schizophrenia are treated with the use of antipsychotic medication, which can be effective at managing psychotic symptoms. Generally, an atypical, also known as second-generation, antipsychotic medication will be prescribed, such as risperidone, olanzapine, and aripiprazole.

People tend to respond to medications differently, so what is effective for one person might not be helpful for someone else. As such, it is common for more than one medication, or a combination of medications, to be utilized before an effective treatment is found.

Clozapine is a unique type of antipsychotic, that is usually only prescribed if two or more medications have been tried with no success. Clozapine is often very effective at treating symptoms of schizophrenia, but can cause serious side effects, so is not prescribed as a first-line treatment. Clozapine treatment will require careful physical health monitoring, such as regular blood tests [8].

Antipsychotic medications often cause side effects, some of which can be very unpleasant. This can cause people to choose not to take their medication. Similarly, many people with schizophrenia may be unaware that they are unwell, causing them to think they don’t need medication. Forgetting or choosing not to take medication is often a cause of relapse [6].

Therefore, it is vital for treatment that medications are taken exactly as directed, as taking too much, missing doses, or suddenly stopping medication can cause adverse effects and may worsen your symptoms.


In some cases, therapy can be a useful treatment for schizophrenia. However, people who experience paranoia may be reluctant to attend therapy, so this may not be an appropriate treatment for all.

Cognitive behavioral therapy (CBT) focuses on challenging harmful thoughts and behaviors, gaining insight and understanding, and helping to prevent relapse [8].

Family therapy might be helpful for some, as it aims to improve communication within the family, while providing education around schizophrenia, including symptoms and behavior [13].

Psychosocial treatments are often useful for those with schizophrenia, as they can provide skills for social and professional development, helping medication compliance, and obtaining information and understanding around the condition [7].


There are several self-care techniques that can be used to help in the treatment of schizophrenia, such as:

  • Avoiding drugs and alcohol: Research shows that substance and alcohol use can impact mental health, make treatments less effective, and potentially cause a relapse. There is also a risk of interaction with antipsychotic medication, which can lead to serious risks and effects on physical and mental health [10].
  • Attending all appointments: For the best chance of recovery, it is important to attend all doctor and therapy appointments, to ensure you are receiving appropriate treatment and that your physical and mental health is being monitored.
  • Getting enough sleep: Having a good night’s sleep is very important for mental and physical wellbeing. A lack of good quality sleep can lead to a worsening in symptoms, so it is often helpful to develop a routine, going to bed and waking up at the same time each day and getting around 8 hours of sleep per night.
  • Being active: It can be helpful to engage in hobbies and activities that you enjoy, as this can improve mental wellbeing. This might include relaxation exercises, yoga, meditation, walking, running, and attending social events.

Other types of schizophrenia

The five subtypes of schizophrenia are no longer used in diagnosis, although the symptoms of each type may still be utilized to formulate a diagnosis. Along with paranoid schizophrenia, the other four previously used subtypes were [1]:

Catatonic schizophrenia

Catatonic schizophrenia is characterized by unusual psychomotor function, which may include odd and unusual movements or postures, an inability to move, or excessive or hyperactive movements [1].

Someone with catatonic schizophrenia might be likely to experience symptoms such as immobility, or stupor, causing them to appear frozen in place, sometimes for prolonged periods of time, or they may hold odd positions for several hours.

Other symptoms that are common with catatonic schizophrenia include echolalia, mimicking other people’s words, and echopraxia, mimicking other people’s actions [14].

Disorganized schizophrenia

Disorganized schizophrenia may include the presence of hallucinations and delusions, with primary presenting symptoms of disorganized speech and behavior [1]. This might include quickly changing topics during conversation, saying bizarre things, repeating words and phrases, or often feeling confused.

Someone with disorganized schizophrenia might also be flat in affect, such as showing no emotion or responding inappropriately or in an unusual manner.

Residual schizophrenia

Residual schizophrenia would be diagnosed when there was no longer a presence of positive symptoms, such as hallucinations and delusions, but a clear disturbance in cognition remains. Someone with residual schizophrenia might experience odd beliefs and negative symptoms.

Undifferentiated schizophrenia

For a diagnosis of undifferentiated schizophrenia, some symptoms of schizophrenia are present, but the condition does not meet the criteria for any of the other subtypes.

  1. American Psychiatric Association. (1994). Diagnostic and Statistical Manual of Mental Disorders (DSM-IV). Washington, DC: American Psychiatric Association.
  2. American Psychiatric Association. (2013, text revision 2022). Schizophrenia spectrum and other psychotic disorders. In The Diagnostic and Statistical Manual of Mental Disorders (5th ed., text rev.). APA. Retrieved from
  3. American Psychiatric Association. (2013). Highlights of changes from DSM-IV-TR to DSM-5. Psychiatry. Retrieved from
  4. Kiran, C., & Chaudhury, S. (2009). Understanding delusions. Industrial Psychiatry Journal18(1), 3-18.
  5. Pinkham, A.E., Harvey, P.D., & Penn, D.L. (2016). Paranoid individuals with schizophrenia show greater social cognitive bias and worse social functioning than non-paranoid individuals with schizophrenia. Schizophrenia Research. Cognition3, 33–38.
  6. Krzystanek, M., Krysta, K., & Skałacka, K. (2017). Treatment compliance in the long-term paranoid schizophrenia telemedicine study. Journal of Technology in Behavioral Science, 2, 84–87.
  7. National Alliance on Mental Health (NAMI). Schizophrenia. NAMI. Retrieved from
  8. Hany, M., Rehman, B., Azhar, Y., & Chapman, J. (2022). Schizophrenia. In: StatPearls [Internet]. Treasure Island, FL: StatPearls Publishing. Retrieved from
  9. Wong, V., Chin, K., & Leontieva, L. (2022). Multifactorial causes of paranoid schizophrenia with auditory-visual hallucinations in a 31-Year-old male with history of traumatic brain injury and substance abuse. Cureus14(5), e25488.
  10. National Institute of Mental Health. (n.d). Schizophrenia. NIH. Retrieved from
  11. Stilo, S.A., & Murray, R.M. (2019). Non-genetic factors in schizophrenia. Current Psychiatry Reports, 21(100).
  12. Marconi, A., Di Forti, M., Lewis, C.M., Murray, R.M., & Vassos, E. (2016). Meta-analysis of the association between the level of cannabis use and risk of psychosis. Schizophrenia Bulletin42(5), 1262–1269.
  13. Patel, K.R., Cherian, J., Gohil, K., & Atkinson, D. (2014). Schizophrenia: overview and treatment options. P & T: A Peer-Reviewed Journal for Formulary Management39(9), 638–645. Retrieved from
  14. Jain, A., & Mitra, P. (2022). Catatonic schizophrenia. In: StatPearls [Internet]. Treasure Island, FL: StatPearls Publishing. Retrieved from
Medical Content

Our Medical Affairs Team is a dedicated group of medical professionals with diverse and extensive clinical experience who actively contribute to the development of our content, products, and services. They meticulously evaluate and review all medical content before publication to ensure it is medically accurate and aligned with current discussions and research developments in mental health. For more information, visit our Editorial Policy.

About is a health technology company guiding people towards self-understanding and connection. The platform offers reliable resources, accessible services, and nurturing communities. Its mission involves educating, supporting, and empowering people in their pursuit of well-being.

Naomi Carr
Author Naomi Carr Writer

Naomi Carr is a writer with a background in English Literature from Oxford Brookes University.

Published: Jan 17th 2023, Last edited: Oct 27th 2023

Dr. Jenni Jacobsen, PhD
Medical Reviewer Dr. Jenni Jacobsen, PhD LSW, MSW

Dr. Jenni Jacobsen, PhD is a medical reviewer, licensed social worker, and behavioral health consultant, holding a PhD in clinical psychology.

Content reviewed by a medical professional. Last reviewed: Jan 17th 2023