Schizophreniform disorder is characterized by symptoms identical to those of schizophrenia but that last ≥ 1 month but < 6 months.

Psychosis refers to symptoms such as delusions, hallucinations, disorganized thinking and speech, and bizarre and inappropriate motor behaviour (including catatonia) that indicate loss of contact with reality. (See also Introduction to Schizophrenia and Related Disorders.)

At presentation, schizophrenia is likely to be suspected. Psychosis secondary to substance use or to a physical disorder must also be ruled out. Differentiating between schizophreniform disorder and schizophrenia in a patient without any prior psychotic symptoms is based on the duration of symptoms. If the duration of symptoms or disability exceeds 6 months, the patient no longer meets the required diagnostic criteria for schizophreniform disorder, and the diagnosis is likely to be schizophrenia, although the acute psychosis may also evolve into a psychotic mood disorder, such as bipolar disorder or schizoaffective disorder. Longitudinal observation is often required to establish the diagnosis and appropriate treatment.

Treatment with antipsychotics and supportive psychosocial care are indicated. After symptoms resolve, drug treatment is continued for 12 months and then gradually tapered while closely monitoring for the return of psychotic symptoms.