Fluphenazine Dosage

Medically reviewed by Drugs.com. Last updated on Jul 24, 2023.

Usual Adult Dose for Psychosis

Oral:

• Initial dose: 2.5 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

Oral Comments:

• 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.

Parenteral:
Fluphenazine Decanoate for Injection:

• Initial dose: 12.5 to 25 mg deep IM injection into the gluteal region
• Maintenance dose: 12.5 to 100 mg IM, usually every 3 to 4 weeks
• Maximum dose: 100 mg/injection

Fluphenazine HCl for Injection:

• Initial dose: 2.5 to 10 mg IM, given as divided doses every 6 to 8 hours
• Maximum dose: Up to 10 mg/day

Parenteral Comments:

• 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.

Uses:

• Management of manifestations of schizophrenia
• Management of patients requiring prolonged parenteral neuroleptic therapy (e.g., patients with chronic schizophrenia)

Usual Geriatric Dose for Psychosis

Oral:

• Initial dose: 1 to 2.5 mg orally, given in divided doses every 6 to 8 hours
• Maintenance dose: 1 to 5 mg/day
• Maximum dose: Up to 40 mg

Comments:

• Maintenance doses may be given as a single dose.
• Many patients achieve therapeutic effect with doses less than 20 mg. Patients who are severely disturbed or inadequately controlled may require a dose of up to 40 mg/day.

Use: Management of manifestations of schizophrenia

Renal Dose Adjustments

Renal insufficiency: Use with caution.
Abnormal BUN: Discontinue treatment

Liver Dose Adjustments

Liver damage: Contraindicated
Development of cholestatic jaundice during treatment: Discontinue use

Dose Adjustments

• Severe neutropenia (absolute neutrophil count less than 1000 mm3): Discontinue treatment and follow WBC counts until recovery occurs

Precautions

US BOXED WARNING:

• INCREASED MORTALITY IN ELDERLY PATIENTS WITH DEMENTIA-RELATED PSYCHOSIS: This drug has an increased risk of mortality when administered to elderly patients with dementia-related psychosis. Elderly patients with dementia-related psychosis treated with antipsychotic drugs have an increased risk of death. This drug is not approved for use in patients with dementia-related psychosis.

Safety and efficacy have not been established in children.

Consult WARNINGS section for additional precautions.

Dialysis

Data not available

Other Comments

Administration advice:

• Decanoate formulations: Dry needles and syringes should be used to prevent cloudiness observed when wet needles and/or syringes are used. The dose should be given as a deep IM injection into the gluteal region.
• Oral solution formulations: The oral solution should be diluted in at least 60 mL (2 fluid ounces) of tomato/fruit juice, milk, and/or uncaffeinated soft drinks prior to administration. Dilution with caffeinated beverages, tannics (e.g., tea), and pectinates (e.g., apple juice) should be avoided.

Storage requirements:

• See manufacturer product information.

Reconstitution/preparation techniques:

• See manufacturer product information.

IV compatibility:

• See manufacturer product information.

General:

• This drug should not be used in non-psychotic disorders.
• Treatment has not been effective in managing behavioral complications in patients with mental disabilities.
• Patients should be started on a short-acting formulation before administering long-acting parenteral formulations.

Monitoring:

• ECG monitoring for patients at risk of QT prolongation or with/with a family history of cardiovascular disease
• Periodic WBC with differential tests, especially in patients with signs/symptoms of infection/sore throat, at increased risk of blood dyscrasias, and/or with a history of low WBCs or drug-induced neutropenia/leukopenia
• Periodic liver function tests
• Blood pressure, especially in patients with impaired cardiovascular systems
• Eye examinations, especially in patients on prolonged treatment with moderate to high doses
• Heart rate, especially in patients with arrhythmias and/or taking QT prolonging drugs concurrently
• Periodic renal function tests, especially in patients on prolonged treatment

Patient advice:

• Patients should be warned to avoid abrupt discontinuation of this drug.
• Patients should be instructed to immediately report any signs/symptoms of neutropenia/leukopenia, neuroleptic malignant syndrome, or tardive dyskinesia.
• Patients should be warned about extrapyramidal reaction signs/symptoms before beginning treatment.
• Patients should be advised to speak to a healthcare provider if they are pregnant, intend to become pregnant, or are breastfeeding.
• Inform patients that this drug may cause drowsiness, and they should avoid driving or operating machinery until the full effects of the drug are seen.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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