Schizophrenia Latest Facts: Causes, Symptoms, Diagnosis and Treatment

Key Takeaways:

Schizophrenia involves disruptions in dopamine, glutamate, and GABA signaling in the brain.
Both genetic factors and early-life stress increase the risk of developing the disorder.
Positive symptoms include hallucinations and delusions; negative symptoms affect motivation and emotion.
Antipsychotic medication and therapy are essential for managing long-term outcomes.

What Is Schizophrenia and Who Does It Affect?

Schizophrenia is a serious mental disorder that affects an individual’s interpretation of reality, affecting everything from the way they think to what they feel. It is characterized by episodes of psychosis associated with hallucinations, delusions, and confusion.

Schizophrenia

It is a mental illness that makes it difficult for patients to realize what is real and what is not. It can decrease the quality of life and requires a lifetime of treatment to prevent symptoms. It is also very common, affecting approximately 20 million individuals worldwide in 2019.

What are the causes of schizophrenia?

Schizophrenia is a multifactorial disorder, with genetics, environmental factors, substance abuse, and many other risk factors playing an important role in the development of this mental illness.

Genetics

Having a first-degree relative with schizophrenia is the greatest risk for an individual to develop schizophrenia. Various genes are also linked with a high risk for schizophrenia. However, it is believed that several small changes in the different alleles of a person’s genetic makeup result in the development of this mental illness. Furthermore, they also believe there is a high involvement of CNVs, which are responsible for other genetic disorders like DiGeorge syndrome and Burnside-Butler Syndrome. These CNVs can increase the risk by 20-fold and usually result in an individual with autism and schizophrenia (Szecówka et al., 2023).

Microdeletions and duplications of various genes together can result in schizophrenia in most cases.

Many genes have been found associated with schizophrenia and the different symptoms of the disorder. Suicidal tendencies and their severity can be analyzed by the CRHR1 and CRHBP genes (De Luca et al., 2008, p. 680).

The question scientists are now trying to answer is the extent of genetic involvement in the development of the disorder, and if the percentage of involvement is high, what is the inheritance pattern of the disorder?

Environmental Factors

Many risk factors fall under this category, but it is important to note that all these risk factors are only associated with a slight increase in risk for the development of schizophrenia.

ACE (Adverse Childhood Experiences): Childhood trauma, whether it’s bullying or the death of a loved one, can result in the development of toxic stress and mental illnesses as an adult. Schizophrenia has been associated with ACEs, although further studies are being performed.
Infections during pregnancy: Pregnant women with herpes simplex, cytomegalovirus, or Toxoplasma gondii can give birth to infants with a higher risk of developing schizophrenia than infants born to healthy mothers. (Brown & Derkits, 2010)
Oxygen deprivation
Prenatal infections
Malnutrition: Mothers who are malnourished during pregnancy also give birth to infants with a higher risk of schizophrenia than normal mothers.
Social isolation or dysfunctional families: Although this can be classified as ACEs.
Vitamin D deficiency.

Some of the risk factors that are yet under research but show a positive relation are pollution, fathers older than 40, parents younger than 20, and even racial discrimination from a young age. The latter can also be classified under ACEs, however, more studies need to be conducted for that to be done.

Substance Abuse

Schizophrenia incidence is higher in individuals using recreational drugs, including cigarette smoking and cannabis smoking. Hard drugs like cocaine and meth may result in a temporary psychosis that resembles schizophrenia. Alcohol can cause mental and cognitive dysfunction like that seen in Wernicke-Korsakoff Syndrome.
Cannabis use can increase the risk of developing schizophrenia, especially if genetic alterations are present. Further studies need to be performed to understand the mechanism of schizophrenia associated with drug use.

What is the pathophysiology of schizophrenia?

Schizophrenia is a mental disorder involving the dysfunction of dopaminergic, glutamatergic, and GABAergic pathways. Misfiring of dopaminergic neurons and misinterpretation of these signals by the brain is the most commonly accepted model for psychosis in schizophrenia. This also causes hallucinations.

Working memory deficit seen in schizophrenia can also be explained by D1 receptors in the prefrontal cortex. However, abnormal activity at D2R is more associated with schizophrenia symptoms than D1R. The extrapyramidal motor symptoms seen in schizophrenia can also be explained by low dopamine levels.

Researchers also found a link between the most important excitatory neurotransmitter, glutamate, and schizophrenia. They made the link between these two after noticing the effect of glutamate-blocking drugs on the brain. Researchers observed that glutamate-blocking drugs, such as ketamine, can induce schizophrenia-like symptoms, highlighting glutamate’s possible role. In fact, many patients taking drugs like ketamine and phencyclidine start presenting with symptoms similar to those of schizophrenia, indicating a link between glutamate levels and the pathophysiology of schizophrenia.

What are the signs and symptoms of schizophrenia?

Schizophrenia is a mental disorder that can affect the way a person perceives reality. They can produce a variety of symptoms, which are usually classified as positive, negative, and cognitive symptoms:

Negative Symptoms: It refers to the lack of a normal emotional response and includes avolition, anhedonia, and alogia. Attention deficit and poor attention span are usually considered negative symptoms as well.
Cognitive Symptoms: These are the earliest symptoms of schizophrenia and usually include memory loss, loss of reasoning, and problem-solving skills, along with increased time for processing of information.
Positive symptoms: Also known as psychosis symptoms, these are the symptoms seen during a psychotic episode. These types of symptoms can be further divided into positive psychotic symptoms and positive disorganization symptoms.

a. Psychotic symptoms: This includes hallucinations, whether auditory, visual, or tactile, olfactory, and/or gustatory, and delusions with distortion of oneself. Hearing voices or auditory hallucinations is the most common.

b. Disorganization symptoms: Also known as thought disorders, it can include disorganized thoughts, language, speech, or behavior

How is schizophrenia diagnosed?

The onset of schizophrenia is usually during the third decade of an individual’s life. Onset before that is referred to as early-onset, and onset after, in the 40s to 60s, is called late-onset schizophrenia.

If schizophrenia symptoms appear before the age of 13, it is known as childhood schizophrenia.

Diagnosis of schizophrenia can be made using the criteria with either the Diagnostic and Statistical Manual of Mental Disorders (DSM) published by the American Psychiatric Association or the International Statistical Classification of Diseases and Related Health Problems (ICD) published by the World Health Organization. For DSM, two diagnostic criteria must be met within one month, one of which should be a positive symptom, and the other can be either cognitive or negative symptoms.

DSM, after recent studies, has included a dimensional assessment that helps with treatment and diagnosis.

Differential diagnosis of schizophrenia

Psychosis is one of the prominent symptoms of schizophrenia and is usually associated with many other diseases, making diagnosing schizophrenia difficult.

Bipolar disorder
Borderline personality disorder
Intoxication
Substance-induced psychosis
Drug withdrawal syndromes
OCD
Alzheimer’s disease
Huntington’s disease
Frontotemporal dementia
Lewy body dementia

How is schizophrenia treated?

Treatment of schizophrenia depends on antipsychotic medications and psychosocial interventions.

Antipsychotic Medications

Due to the active role of dopamine in the development of schizophrenia, the use of typical antipsychotic drugs like dopamine antagonists can be very beneficial. There are also atypical antipsychotic medications that affect serotonin and help in the treatment of schizophrenia. These drugs reduce the positive symptoms, however, they have no effect on negative or cognitive symptoms. In 2019, the FDA approved a new drug named lumateperone, which affects multiple neurotransmitter systems and is beneficial in treating schizophrenia.
It is important to note that these medications can produce strong side effects like movement disorders, tiredness and fatigue, and weight gain, and should be taken only when prescribed with close follow-ups.

Psychosocial Interventions

Psychotherapy: It can be really beneficial for behavioral problems associated and usually includes: family therapy, group therapy, CBT, and metacognitive therapy.

Assertive Community Treatment (ACT): This usually includes helping affected individuals find housing, managing finances, and also providing assistance with daily life tasks like medication management, shopping, and so on. It has shown great results.

Exercise Therapy: It has shown some positive results, especially with cognitive symptoms like memory and attention deficit

Preventive Perspective

Schizophrenia is a mental disorder that can affect individuals who are genetically predisposed and have risk factors like smoking and nutritional deficits. It is important to quit smoking and avoid cannabis smoking as they can, in the long run, both cause serious consequences and negatively impact the quality of life. Since genetic predisposition to schizophrenia can result in the disorder in the presence of other risk factors, living a healthy life can prevent the development of schizophrenia and should be highly recommended.

Frequently Asked Questions About Schizophrenia

What is schizophrenia?
A chronic mental illness that affects how a person thinks, feels, and perceives reality. It often involves hallucinations, delusions, disorganized thinking, and cognitive impairment.

Is it the same as having multiple personalities?
No. That’s a myth. Schizophrenia is not related to dissociative identity disorder (split personality).

What causes schizophrenia?
It’s multifactorial: genetic vulnerability, brain chemistry (dopamine, glutamate, GABA), early trauma, infections during pregnancy, and possibly high-stress environments all contribute.

What role do genetics play?
Having a first-degree relative with schizophrenia increases your risk. Certain genetic deletions or duplications (like 22q11.2 deletion syndrome) are linked to higher susceptibility.

Does cannabis use increase the risk?
Yes, especially high-potency cannabis used during adolescence. It may trigger schizophrenia in genetically at-risk individuals (Marconi et al., 2016). Legalization doesn’t make it risk-free.

When does schizophrenia usually start?
Most often in the late teens to early 30s. Onset before age 13 is rare and called childhood-onset schizophrenia.

What are the early signs?
Social withdrawal, trouble focusing, emotional flatness, unusual thoughts, and disrupted sleep can all be prodromal signs.

What are positive symptoms?
These include hallucinations (usually auditory), delusions, paranoia, and disorganized speech or behavior.

What are negative symptoms?
Lack of motivation, social withdrawal, reduced speech (alogia), and emotional flatness.

What are cognitive symptoms?
Trouble with memory, decision-making, attention, and understanding information. These often persist even when psychotic symptoms improve.

How is schizophrenia diagnosed?
Using DSM-5 or ICD-11 criteria. Symptoms must last for at least six months with at least one psychotic feature (like hallucinations or delusions) present for one month.

What are some conditions that mimic schizophrenia?
Bipolar disorder, major depression with psychosis, substance-induced psychosis, borderline personality disorder, Alzheimer’s, frontotemporal dementia, and others.

What medications are used?

First-generation antipsychotics: haloperidol, chlorpromazine — good for positive symptoms but more motor side effects.
Second-generation (atypical) antipsychotics: risperidone, olanzapine, quetiapine, aripiprazole — broader action with fewer motor side effects but risk of weight gain and metabolic syndrome.
Treatment-resistant cases: Clozapine is often used when others fail.
Newest options: lumateperone and cariprazine — these target multiple neurotransmitters and show fewer side effects in trials.

Do antipsychotics treat all symptoms?
Mostly positive symptoms. Negative and cognitive symptoms often remain and require therapy, routine, and rehabilitation programs.

What are the side effects of medication?
They vary but may include drowsiness, tremors, weight gain, increased blood sugar, restlessness (akathisia), or sexual dysfunction.

What happens if I stop taking medication?
Relapse is common. Stopping abruptly without medical supervision is strongly discouraged.

Are there treatments beyond medication?
Yes. Psychosocial therapy, cognitive behavioral therapy (CBT), social skills training, supported employment, and exercise programs help with long-term functioning.

What are some newer treatments in development?

Glutamate modulators (e.g., glycine transporter inhibitors) to target cognitive symptoms (Moghaddam & Javitt, 2012).
Anti-inflammatory agents to reduce neuroinflammation (Sommer et al., 2014).
Non-invasive brain stimulation (e.g., transcranial magnetic stimulation) shows promise for negative (Dougall et al., 2015).
Microbiome research may open new probiotic-based strategies in the future (Kelly et al., 2021).

Can people with schizophrenia work or study?
Yes, with treatment and support. Many return to school or jobs, especially when symptoms are well-managed.

Can I live independently?
Often, yes. Some need support, but many live on their own with medication and outpatient care.

Can I drive?
If symptoms are stable and you’re not overly sedated, yes. Avoid driving during active episodes or while adjusting medication.

Can I have children?
Yes. Schizophrenia doesn’t prevent parenting, but it helps to plan carefully and ensure stability. Talk to a provider about risks and support needs.

Is schizophrenia linked to violence?
Only in rare, untreated cases. Most people with schizophrenia are more likely to be victims than perpetrators.

What should families know?
Education is key. Learn early signs, encourage treatment, attend family therapy if possible, and support rather than pressure.

What’s a psychotic break?
A period when someone loses touch with reality, often with hallucinations or delusions. Immediate treatment helps shorten the episode.

What is clozapine and why is it special?
Clozapine is the most effective antipsychotic for treatment-resistant schizophrenia but requires regular blood monitoring due to rare side effects like agranulocytosis.

What does “managing” schizophrenia mean?
It means reducing symptoms, preventing relapse, improving quality of life, and increasing independence, not “curing” the illness.

Can schizophrenia be prevented?
Not completely, but early treatment, avoiding drugs like cannabis, and reducing stress may lower risk or delay the onset in vulnerable individuals.

What are prodromal symptoms?
Subtle early warning signs before full psychosis, like mood swings, paranoia, or social withdrawal.

What is insight in schizophrenia?
Insight means recognizing that you’re ill. Many patients initially lack insight, making treatment harder. It often improves with care.

What happens during a relapse?
Old symptoms return—hallucinations, delusions, or confusion. Early signs include sleep problems, isolation, or increased suspicion.

What’s the long-term outlook?
Varies. Some live with mild symptoms and work full-time; others may need long-term support. Early intervention improves outcomes.

Where can I get help right now?
In the U.S., call 911 in an emergency or the Suicide & Crisis Lifeline at 988. For non-emergencies, contact a psychiatrist or mental health clinic.

Final Thoughts: The Road Ahead for Schizophrenia Care

Schizophrenia research is evolving rapidly. While dopamine-targeting antipsychotics remain central, newer approaches are exploring glutamate modulation, anti-inflammatory pathways, and even personalized interventions based on genetic risk. Digital therapies, brain stimulation techniques, and early detection models offer promising ways to intervene before full-blown symptoms take hold.

Another pressing concern is the rise in cannabis use, particularly among teens and young adults. As legalization expands globally, researchers are seeing growing evidence that high-potency cannabis, especially when used frequently or in adolescence, may increase the risk of developing schizophrenia in genetically vulnerable individuals. Public health messaging will need to catch up with legal trends to ensure that informed choices are made, especially by those at risk.

Still, the overall outlook for patients is more hopeful than ever. With early treatment, adherence, and community support, many people with schizophrenia can build stable, fulfilling lives. The focus is shifting from symptom control to recovery, autonomy, and quality of life—transforming how we think about what’s possible after diagnosis.

**Warning: Some symptoms require emergency care. If someone is thinking about hurting themselves or others or trying to kill themselves, look for help immediately:

Call 911 for emergency services or go to the nearest emergency room.
Call the National Suicide Prevention Lifeline (Lifeline) at 1-800-273-TALK (8255) or text the Crisis Text Line (text HELLO to 741741).

References

National Institute of Mental Health. (n.d.). Schizophrenia. U.S. Department of Health and Human Services, National Institutes of Health. Retrieved April 23, 2025, from https://www.nimh.nih.gov/health/topics/schizophrenia

Szecówka, K., Misiak, B., Łaczmańska, I., Frydecka, D., & Moustafa, A. A. (2023). Copy number variations and schizophrenia. Molecular Neurobiology, 60(4), 1854–1864. https://doi.org/10.1007/s12035-022-03185-8

De Luca, V., Tharmalingam, S., Zai, C., et al. (2008). Association of HPA axis genes with suicidal behaviour in schizophrenia. Journal of Psychopharmacology, 24(5), 677–682. https://doi.org/10.1177/0269881108097817

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 Bulletin, 42(5), 1262–1269. https://doi.org/10.1093/schbul/sbw003

Brown, A. S., & Derkits, E. J. (2010). Prenatal infection and schizophrenia: A review of epidemiologic and translational studies. American Journal of Psychiatry, 167(3), 261–280. https://doi.org/10.1176/appi.ajp.2009.09030361

Iris E. Sommer, Roos van Westrhenen, Marieke J. H. Begemann, Lot D. de Witte, Stefan Leucht, René S. Kahn, Efficacy of Anti-inflammatory Agents to Improve Symptoms in Patients With Schizophrenia: An Update, Schizophrenia Bulletin, Volume 40, Issue 1, January 2014, Pages 181–191, https://doi.org/10.1093/schbul/sbt139

Kelly, J. R., Minuto, C., Cryan, J. F., Clarke, G., & Dinan, T. G. (2021). The role of the gut microbiome in the development of schizophrenia. Schizophrenia Research, 234, 4–23. https://doi.org/10.1016/j.schres.2020.02.010

Moghaddam, B., Javitt, D. From Revolution to Evolution: The Glutamate Hypothesis of Schizophrenia and its Implication for Treatment. Neuropsychopharmacol 37, 4–15 (2012). https://doi.org/10.1038/npp.2011.181

Dougall, N., Maayan, N., Soares-Weiser, K., McDermott, L. M., & McIntosh, A. (2015). Transcranial magnetic stimulation (TMS) for schizophrenia. Cochrane Database of Systematic Reviews, 2015(8), Article CD006081. https://doi.org/10.1002/14651858.CD006081.pub2