Clinical Overview
Perphenazine is a phenothiazine antipsychotic indicated for the treatment of schizophrenia and for controlling severe nausea and vomiting in adults. It represents one of the classical typical antipsychotics with proven efficacy but significant side effect considerations that require careful monitoring.
Primary Clinical Applications
Perphenazine is indicated for schizophrenia management and severe nausea/vomiting control. It is particularly useful in patients who require antipsychotic treatment but may not tolerate newer atypical agents, though it carries higher risk of extrapyramidal symptoms.
Mechanism and Clinical Considerations
As a dopamine D2 receptor antagonist, perphenazine effectively manages psychotic symptoms but also blocks dopamine in other brain regions, leading to extrapyramidal side effects. The medication also has antiemetic properties through dopamine blockade in the chemoreceptor trigger zone.
Monitoring Requirements
Regular monitoring for tardive dyskinesia, extrapyramidal symptoms, and metabolic effects is essential. The medication requires careful dose titration and consideration of individual patient risk factors.
Prescribing Information
Dosing & Administration
Schizophrenia:
- Outpatients: 4-8 mg three times daily
- Hospitalized patients: 8-16 mg 2-4 times daily
- Maximum: 64 mg daily
- Maintenance: Reduce to lowest effective dose
Severe Nausea/Vomiting:
- Adults: 8-16 mg daily in divided doses
- Maximum: 24 mg daily
Elderly:
- Use lower doses and increase gradually
- Monitor closely for adverse effects
Indications
- Schizophrenia
- Severe nausea and vomiting in adults
Contraindications
- Comatose states
- Severe CNS depression
- Blood dyscrasias
- Bone marrow depression
- Liver damage
- Subcortical brain damage
Warnings & Precautions
- Boxed Warning: Increased mortality in elderly patients with dementia-related psychosis
- Tardive dyskinesia: Risk increases with duration of treatment
- Neuroleptic malignant syndrome: Rare but potentially fatal
- QT prolongation/TdP risk: Avoid in patients with known QT prolongation, congenital long QT syndrome, significant bradycardia, recent MI, uncompensated heart failure, electrolyte abnormalities, or when used with other QT-prolonging drugs; use the lowest effective dose
- Extrapyramidal symptoms: Common, dose-related
Drug Interactions
- CNS depressants: Enhanced sedation and respiratory depression
- Anticholinergic drugs: Additive anticholinergic effects
- Lithium: Increased risk of extrapyramidal symptoms
- QT-prolonging drugs: Increased arrhythmia risk
Adverse Reactions
Common:
- Extrapyramidal symptoms, sedation, anticholinergic effects
Serious:
- Tardive dyskinesia, neuroleptic malignant syndrome, agranulocytosis
Special Populations
- Elderly: Increased mortality risk in dementia-related psychosis
- Pregnancy: Use only if benefits outweigh risks
- Hepatic impairment: Contraindicated in liver damage
Medical Disclaimer: This information is for educational purposes only and is not intended as medical advice. Always consult with qualified healthcare professionals before making any treatment decisions. Individual patient circumstances may vary significantly.
