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Fluphenazine Dosage

Applies to the following strength(s): decanoate 25 mg/mL ; 2.5 mg/mL ; 5 mg/mL ; 2.5 mg/5 mL ; enanthate 25 mg/mL ; 1 mg ; 2.5 mg ; 5 mg ; 10 mg

The information at is not a substitute for medical advice. Always consult your doctor or pharmacist.

Usual Adult Dose for:

Usual Geriatric Dose for:

Additional dosage information:

Usual Adult Dose for Psychosis

Oral: Initial dose: 0.5 to 10 mg/day orally in divided doses every 6 to 8 hours.
Maintenance dose: A daily dose in excess of 3 mg is rarely necessary. Once symptoms have been controlled, the dosage should be gradually reduced to a daily maintenance dose of 1 to 5 mg which can often be administered as a single daily dose.

Parenteral: Initial dose: 2.5 to 10 mg/day IM divided every 6 to 8 hours (2.5 mg/mL).
Enanthate/Decanoate (25 mg/mL): Initial dose: 12.5 to 25 mg IM or subcutaneously.
Maintenance dose: Administer enanthate/decanoate dose usually every 3 to 4 weeks.

Usual Geriatric Dose for Psychosis

Initial dose: 1 to 2.5 mg/day orally in divided doses every 6 to 8 hours.

Renal Dose Adjustments

Renal dysfunction: Caution is recommended
Renal failure: Contraindicated

Liver Dose Adjustments

Liver dysfunction: Caution is recommended
Liver failure: Contraindicated

Dose Adjustments

When symptoms are controlled, reduce gradually to a daily dose of 1 to 5 mg. The IM dose is approximately one third to one half of the oral dose.
Enanthate/Decanoate: If doses greater than 50 mg are needed, increase dose cautiously in 12.5 mg increments.


Initially treat patients who have never taken phenothiazines with a shorter-acting form of the drug before using the enanthate or decanoate.


Data not available

Other Comments

Use daily doses in excess of 20 mg orally or 10 mg IM with caution. Do not exceed 100 mg/dose of enanthate or decanoate.