Schizophrenia is a chronic mental disorder defined by periods of psychosis and disturbed thoughts and behavior lasting over 6 months. It involves an inability to distinguish between reality and delusions. Diagnosis requires 2 or more symptoms such as hallucinations, disorganized behavior, or negative symptoms. Schizophrenia has no single cause but is thought to involve genetic and environmental factors. It affects over 2 million Americans and has enormous societal costs due to disability and healthcare expenses. Treatment involves antipsychotic medication to control symptoms, though medication may have dangerous side effects.