What is the use of fluphenazine (Fluphenazine, a typical antipsychotic medication)?

From the Guidelines

Fluphenazine should be used with caution in patients with schizophrenia due to its potential for significant side effects, and its use should be guided by the most recent and highest quality evidence, such as the American Psychiatric Association's practice guideline for the treatment of patients with schizophrenia 1.

Overview of Fluphenazine

Fluphenazine is a first-generation (typical) antipsychotic medication used primarily to treat schizophrenia and other psychotic disorders. It works by blocking dopamine receptors in the brain, particularly D2 receptors, which helps reduce symptoms like hallucinations, delusions, and disorganized thinking.

Dosage and Administration

Fluphenazine is available in oral forms (tablets) typically dosed at 0.5-10 mg daily in divided doses, and as a long-acting injectable (fluphenazine decanoate) given every 2-4 weeks at doses of 12.5-50 mg. The injectable form is particularly useful for patients with adherence difficulties.

Side Effects and Monitoring

Common side effects include extrapyramidal symptoms (parkinsonian symptoms, akathisia, dystonia), sedation, anticholinergic effects (dry mouth, constipation, blurred vision), and hyperprolactinemia. Patients should be monitored for tardive dyskinesia, a potentially irreversible movement disorder that can develop with long-term use. Blood pressure monitoring is important as orthostatic hypotension can occur, especially when initiating therapy.

Treatment Guidelines

According to the American Psychiatric Association's practice guideline for the treatment of patients with schizophrenia 1, patients with schizophrenia should be treated with an antipsychotic medication and monitored for effectiveness and side effects. The guideline also recommends that patients with treatment-resistant schizophrenia be treated with clozapine, and that patients with schizophrenia be treated with clozapine if the risk for suicide attempts or suicide remains substantial despite other treatments.

Comparison with Other Antipsychotics

While newer antipsychotics (atypicals) are often preferred due to their improved side effect profiles, fluphenazine remains valuable for patients who have responded well to it historically or who haven't responded adequately to newer medications. However, the use of typical antipsychotics like fluphenazine is generally discouraged due to their association with significant side effects, including extrapyramidal symptoms and tardive dyskinesia 1.

• Key points to consider when using fluphenazine include:
  • Close monitoring for side effects, particularly extrapyramidal symptoms and tardive dyskinesia
  • Regular assessment of treatment effectiveness and adjustment of dosage as needed
  • Consideration of alternative antipsychotic medications, particularly atypicals, due to their improved side effect profiles
  • Use of the lowest effective dose to minimize the risk of side effects
  • Patient education on the potential risks and benefits of fluphenazine treatment.

From the FDA Drug Label

INDICATIONS AND USAGE Fluphenazine hydrochloride tablets are indicated in the management of manifestations of psychotic disorders. 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). The main indications for fluphenazine are:

• Management of manifestations of psychotic disorders 2
• Management of patients requiring prolonged parenteral neuroleptic therapy, such as chronic schizophrenics 3

From the Research

Overview of Fluphenazine

• Fluphenazine is an antipsychotic medication used to treat schizophrenia and other psychotic disorders 4, 5.
• It is available in oral and injectable forms, and its efficacy and side effects have been studied in various clinical trials 4, 5.

Efficacy of Fluphenazine

• A study published in 1995 found that fluphenazine was effective in improving positive symptoms of schizophrenia, such as hallucinations and delusions, in patients with acute schizophrenic exacerbations 4.
• However, another study published in 2005 found that fluphenazine was less effective than risperidone and quetiapine in treating patients with therapy-refractory schizophrenia 5.
• The study found that only 15% of patients treated with fluphenazine met response criteria, compared to 23% and 25% of patients treated with risperidone and quetiapine, respectively 5.

Side Effects of Fluphenazine

• Fluphenazine has been associated with several side effects, including extrapyramidal symptoms (EPS), such as akathisia and parkinsonism 4, 5.
• A study published in 1995 found that akathisia was more common and EPS were more severe at higher plasma levels of fluphenazine 4.
• Another study published in 2005 found that side effect occurrence was similar among patients treated with fluphenazine, risperidone, and quetiapine, but that EPS ratings improved in all drug groups 5.

Therapeutic Drug Monitoring

• Therapeutic drug monitoring (TDM) is a growing area of interest for antipsychotic medications, including fluphenazine 6.
• A review published in 2019 found that there is a growing body of evidence to support TDM for fluphenazine, as well as other antipsychotics such as haloperidol, perphenazine, and olanzapine 6.
• The review noted that TDM can help optimize treatment outcomes and minimize side effects, but that more research is needed to standardize methods and establish clear therapeutic reference ranges 6.