Nurses Compass
Drug Guide
Fluphenazine Enanthate
Classification
Therapeutic: Antipsychotic (Neuroleptic)
Pharmacological: Phenothiazine antipsychotic
FDA Approved Indications
- Schizophrenia
Mechanism of Action
Blocks dopamine D2 receptors in the brain, reducing dopaminergic neurotransmission which alleviates symptoms of psychosis.
Dosage and Administration
Adult: Typically 25-50 mg IM every 2 weeks, adjust based on response and tolerability.
Pediatric: Not generally recommended due to limited safety data.
Geriatric: Start at lower doses, monitor closely due to increased sensitivity to side effects.
Renal Impairment: Use with caution; dose adjustments may be necessary based on clinical response.
Hepatic Impairment: Use with caution; monitor liver function and response.
Pharmacokinetics
Absorption: Absorbed via intramuscular injection, with slow release.
Distribution: Widely distributed in body tissues, crosses blood-brain barrier.
Metabolism: Metabolized in liver, primarily by CYP2D6 enzyme.
Excretion: Excreted mainly in urine as metabolites.
Half Life: Approximately 4 days (long-acting injection).
Contraindications
- hypersensitivity to phenothiazines or other components
- Coma
Precautions
- History of blood dyscrasias
- Severe cardiovascular disease
- Parkinson's disease
- History of neuroleptic malignant syndrome
- Elderly patients with dementia-related psychosis (black box warning)
Adverse Reactions - Common
- Extrapyramidal symptoms (Common)
- Drowsiness (Common)
- Dry mouth (Common)
- Dizziness (Common)
Adverse Reactions - Serious
- Neuroleptic malignant syndrome (Rare)
- Tardive dyskinesia (Possible with long-term use)
- Seizures (Rare)
- QT prolongation leading to arrhythmias (Rare)
Drug-Drug Interactions
- Other central nervous system depressants, which can enhance sedative effects
- Anticholinergic agents, which may exacerbate anticholinergic side effects
- CNS stimulants, which may counteract sedative effects
Drug-Food Interactions
- Alcohol may increase sedation and hypotension
Drug-Herb Interactions
N/ANursing Implications
Assessment: Monitor mental status, fluid and electrolyte balance, blood cell counts, and signs of extrapyramidal symptoms.
Diagnoses:
- Risk for falls due to sedation or orthostatic hypotension.
- Risk for neuroleptic malignant syndrome.
Implementation: Administer via intramuscular injection as prescribed. Monitor for side effects and therapeutic response.
Evaluation: Assess improvement in psychotic symptoms and monitor for adverse reactions.
Patient/Family Teaching
- Do not abruptly discontinue medication.
- Report symptoms of movement disorders or neuroleptic malignant syndrome.
- Avoid alcohol and CNS depressants without consulting healthcare provider.
- Attend regular follow-up appointments.
Special Considerations
Black Box Warnings:
- Elderly patients with dementia-related psychosis treated with antipsychotics are at an increased risk of death.
Genetic Factors: Metabolism may vary based on CYP2D6 activity, affecting drug levels.
Lab Test Interference: May cause false-positive results in some diagnostic tests, including serum glucose and cholesterol.
Overdose Management
Signs/Symptoms: Sedation, hypotension, extrapyramidal symptoms, seizures, coma.
Treatment: Supportive care, intravenous fluids, monitoring vital signs and cardiac function, and management of symptoms. In some cases, the use of activated charcoal or specific antidotes may be indicated.
Storage and Handling
Storage: Store at room temperature away from light and moisture.
Stability: Stable for shelf life as indicated by manufacturer.