MH PHARM | Prolixin [Fluphenazine]

Medication Name/Class

• Generic/Brand: Fluphenazine / Prolixin Decanoate
• Class: First-Generation Antipsychotic (Phenothiazine)

2. Mechanism of Action

• Blocks postsynaptic D2 (dopamine) receptors in the mesolimbic system.
• Possesses weak anticholinergic and alpha1-adrenergic blocking effects.
• Strong D2 blockade reduces psychosis but directly causes extrapyramidal symptoms (EPS).

3. Expected Action/Therapeutic Effect

• Decreases dopamine neurotransmission to control psychotic symptoms.
• Provides antiemetic effects by blocking the chemoreceptor trigger zone.

4. Indications

• Priority Uses: Schizophrenia (maintenance and acute management).
• Acute agitation in psychotic disorders.
• Off-Label: Severe behavioral/psychological symptoms of dementia (strictly regulated by OBRA).

5. Pharmacokinetics

• Onset/Peak: Oral peaks in 2 hrs. Immediate IM peaks in 1.5-2 hrs. Depot IM/SubQ peaks in 8-10 hrs.
• Duration: Immediate IM lasts 6-8 hrs; Depot lasts 2-4 weeks.
• Metabolism: Liver; major CYP2D6 substrate and inhibitor.

6. Drug-Drug Interactions

• CNS depressants: Increase sedation and fall risk in the elderly.
• CYP2D6 substrates: Metabolism may be inhibited by fluphenazine.
• Food/Liquid Interaction: Oral concentrate MUST NOT be mixed with caffeine (coffee, cola), tannics (tea), or pectinates (apple juice).

7. Side Effects vs Adverse Effects

• Common: EPS (pseudoparkinsonism, akathisia, dystonia), sedation, anticholinergic effects (dry mouth), orthostatic hypotension.
• Severe/Life-Threatening: Neuroleptic Malignant Syndrome (NMS), Tardive Dyskinesia (TD), prolonged QT/Torsade de pointes, agranulocytosis, seizures.

8. Contraindications/Precautions

• Contraindicated: Hepatic impairment or liver damage.
• Precautions: Geriatric patients (Beers Criteria) due to high risk of falls, fractures, and anticholinergic effects.

9. Nursing Interventions

• Admin: Inject deeply into upper outer gluteal muscle; rotate sites. Do NOT dilute depot injections.
• Safety: Keep patient recumbent for 30 mins post-injection to minimize severe hypotension.
• Monitor: Sodium levels for SIADH risk.

10. Patient Education

• Take oral doses with food if GI upset occurs.
• Avoid spilling liquid preparations on skin/clothing.
• Rise slowly from sitting or lying down to manage orthostatic hypotension.

11. Black Box Warning/Antidote

• BBW: Increased mortality in elderly patients with dementia-related psychosis (deaths usually from heart failure, infections, or stroke).

12. Nursing School Priority Summary

• Must Know: Keep the patient flat for 30 minutes after injection to prevent severe hypotensive effects.
• Nice to Know: 10 mg of daily oral fluphenazine converts to ~12.5 mg of depot every 3 weeks.
• Test Trap: The oral concentrate has strict mixing rules—never mix with coffee, tea, or apple juice.
• Clinical Red Flag: Watch for potentially fatal NMS, TD, and blood dyscrasias.