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Intermediate Technical IVT

first-episode psychosis

Also written as: FEP — First-Episode Psychosis

The initial occurrence of psychotic symptoms in an individual, representing a critical period for intervention and prognosis.

Full Definition

First-episode psychosis (FEP) refers to the first time an individual experiences psychotic symptoms severe enough to meet clinical criteria for a psychotic disorder. This concept is central to psychiatric epidemiology as it represents a clear milestone in disease progression and provides opportunities to study risk factors, early intervention effects, and natural history. FEP typically occurs in late adolescence or early adulthood and is associated with significant functional impairment. Epidemiological studies of FEP inform service planning, help identify high-risk populations, and evaluate the effectiveness of early intervention programs in improving long-term outcomes.

Usage

Usage note: Distinguish from first psychotic episode, which may occur in the context of established illness.

In Context

  • "The incidence of first-episode psychosis peaks during the late teenage years." — Epidemiological report
  • "Early intervention services for first-episode psychosis showed improved outcomes at two-year follow-up." — Treatment evaluation

Also known as

FEP psychotic onset

Contrasted with

chronic psychosis treatment-resistant psychosis

Don't confuse with

first psychotic episode early psychosis prodromal psychosis

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