In order to determine whether the diagnosis of a psychotic disorder is warranted, the health care professional has to first consider if a medical illness may be the cause of the behavioral changes. If a medical disease is identified or the psychosis is found to be the result of exposure to a medication or drug, the sufferer is assessed as having psychotic disorder due to a medical condition or psychotic disorder due to toxin exposure or withdrawal, respectively. On the other hand, if a medical cause and toxin exposure have been looked for and not found, a psychotic illness such as schizophrenia could be considered. The diagnosis will best be made by a licensed mental-health professional (like a psychiatrist or clinical psychologist), who can evaluate the patient and carefully sort through the diagnostic criteria for a variety of mental illnesses that might look alike at the initial examination, like schizotypal or schizoid personality disorder or a mood disorder with psychotic features like severe depression , or the mania phase of bipolar disorder. Other health care professionals who may treat psychotic disorders may include licensed social workers, psychiatric nurses and nurse practitioners, mental health physician assistants, and sometimes non-psychiatric physicians.
-Initial dose: to 10 mg orally in divided doses every 6 to 8 hours
-Maintenance dose: 1 to 5 mg/day
-Maximum dose: Up to 40 mg/day
-Maintenance doses may be given as single daily doses.
-Many patients achieve therapeutic effect with doses of less than 20 mg. Patients who are severely disturbed or inadequately controlled may require a dose of up to 40 mg/day.
Fluphenazine Decanoate for Injection:
-Initial dose: to 25 mg deep IM injection into the gluteal region
-Maintenance dose: to 100 mg IM, usually every 3 to 4 weeks
-Maximum dose: 100 mg/injection
Fluphenazine HCl for Injection:
-Initial dose: to 10 mg IM, given as divided doses every 6 to 8 hours
-Maximum dose: Up to 10 mg/day
-Patients may switch from Fluphenazine HCl for Injection to oral formulations when symptoms are controlled. The dose of an oral formulation is approximately 2 to 3 times the dose of fluphenazine HCl for injection.
-Fluphenazine decanoate for injection may be given subcutaneously.
-Management of manifestations of schizophrenia
-Management of patients requiring prolonged parenteral neuroleptic therapy (., patients with chronic schizophrenia)
Fluphenazine came into use in 1959.  The injectable form is on the World Health Organization's List of Essential Medicines , the most effective and safe medicines needed in a health system .  It is available as a generic medication .  In the United States the tablets costs between and USD per day for a typical dose.  The wholesale cost in the developing world of the long acting form is between and USD per injection as of 2014.  It was discontinued in Australia around mid 2017.