Overview
DESCRIPTION: Fluphenazine decanoate is the decanoate ester of a trifluoromethyl phenothiazine derivative. It is a highly potent behavior modifier with a markedly extended duration of effect and has the following structural formula: C 32 H 44 F 3 N 3 O 2 S Molecular Weight: 591.77 Fluphenazine Decanoate Injection, USP is available as a clear, pale yellow solution for intramuscular (IM) or...
Mechanism of Action
CLINICAL PHARMACOLOGY: The basic effects of fluphenazine decanoate appear to be no different from those of fluphenazine hydrochloride, with the exception of duration of action. The esterification of fluphenazine markedly prolongs the drug’s duration of effect without unduly attenuating its beneficial action. Fluphenazine decanoate has activity at all levels of the central nervous system (CNS) as well as on multiple organ systems. The mechanism whereby its therapeutic action is exerted is unknown. Fluphenazine differs from other phenothiazine derivatives in several respects: it is more potent on a milligram basis, it has less potentiating effect on CNS depressants and anesthetics than do some of the phenothiazines and appears to be less sedating, and it is less likely than some of the...
Indications
- INDICATIONS AND USAGE: Fluphenazine Decanoate Injection is a long-acting parenteral antipsychotic drug intended for use in the management of patients requiring prolonged parenteral neuroleptic therapy (e.g., chronic schizophrenics). Fluphenazine Decanoate Injection has not been shown effective in the management of behavioral complications in patients with mental retardation.
Common Doses
- 25 mg
- 1 mL
- 60 mg
- 20 mg
Dosage
DOSAGE AND ADMINISTRATION: Fluphenazine Decanoate Injection may be given intramuscularly or subcutaneously. A dry syringe and needle of at least 21 gauge should be used. Use of a wet needle or syringe may cause the solution to become cloudy. To begin therapy with Fluphenazine Decanoate Injection, the following regimens are suggested: For most patients , a dose of 12.5 to 25 mg (0.5 to 1 mL) may be given to initiate therapy. The onset of action generally appears between 24 and 72 hours after injection and the effects of the drug on psychotic symptoms becomes significant within 48 to 96 hours.
Black Box Warning
WARNING Increased Mortality in Elderly Patients with Dementia-Related Psychosis — Elderly patients with dementia-related psychosis treated with antipsychotic drugs are at an increased risk of death. Analyses of seventeen placebo-controlled trials (modal duration of 10 weeks), largely in patients taking atypical antipsychotic drugs, revealed a risk of death in drug treated patients of between 1.6 to 1.7 times the risk of death in placebo-treated patients. Over the course of a typical 10-week controlled trial, the rate of death in drug-treated patients was about 4.
Contraindications
- CONTRAINDICATIONS: Phenothiazines are contraindicated in patients with suspected or established subcortical brain damage. Phenothiazine compounds should not be used in patients receiving large doses of hypnotics. Fluphenazine Decanoate Injection is contraindicated in comatose or severely depressed states. The presence of blood dyscrasia or liver damage precludes the use of fluphenazine decanoate. Fluphenazine Decanoate Injection is not intended for use in children under 12 years of age.
Side Effects
- ADVERSE REACTIONS: Central Nervous System The side effects most frequently reported with phenothiazine compounds are extrapyramidal symptoms including pseudoparkinsonism, dystonia, dyskinesia, akathisia, oculogyric crises, opisthotonos, and hyperreflexia. Muscle rigidity sometimes accompanied by hyperthermia has been reported following use of fluphenazine decanoate. Most often these extrapyramidal symptoms are reversible; however, they may be persistent (see below).
Interactions
- No major interactions listed on the FDA label. Always consult a healthcare professional.