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Prolixin Side Effects

Generic name: fluphenazine

Medically reviewed by Last updated on Nov 6, 2023.

Note: This document contains side effect information about fluphenazine. Some dosage forms listed on this page may not apply to the brand name Prolixin.

Applies to fluphenazine: oral elixir, oral solution concentrate, oral tablets, parenteral injection.


    Increased Mortality in Geriatric Patients with Dementia-related Psychosis
  • Geriatric patients with dementia-related psychosis treated with antipsychotic agents are at an increased risk of death.100 101 102 103 c f g i j k l

  • Analyses of 17 placebo-controlled trials in geriatric patients mainly receiving atypical antipsychotic agents revealed an approximate 1.6- to 1.7-fold increase in mortality compared with that in patients receiving placebo.100 c f g i j

  • Most fatalities appeared to result from cardiovascular-related events (e.g., heart failure, sudden death) or infections (mostly pneumonia).b c f g i j

  • Observational studies suggest that conventional or first-generation antipsychotic agents also may increase mortality in such patients.100 c f g i k

  • Antipsychotic agents, including fluphenazine, are not approved for the treatment of dementia-related psychosis.100 101 c f g i j

Side effects include:

Extrapyramidal reactions (e.g., pseudo-parkinsonism, dystonia, dyskinesia, akathisia, oculogyric crises, opisthotonos, hyperreflexia), drowsiness, lethargy, weight gain.

For Healthcare Professionals

Applies to fluphenazine: injectable solution, oral concentrate, oral elixir, oral tablet.


The most commonly reported side effects include extrapyramidal symptoms (e.g., pseudoparkinsonism, dystonia, dyskinesia).[Ref]


Rare (0.01% to 0.1%): Blood dyscrasias

Frequency not reported: Transient leukopenia/leukopenia, thrombocytopenia, leukocytosis, agranulocytosis/fatal agranulocytosis, cellular depression, eosinophilia, pancytopenia, aplastic/hemolytic anemia, thrombocytopenic or nonthrombocytopenic purpura[Ref]


Rare (0.01% to 0.1%): Increased serum cholesterol

Frequency not reported: Hyponatremia, loss of appetite, weight changes, blood glucose level alterations and loss of diabetic control[Ref]


Rare (0.01% to 0.1%): Jaundice

Frequency not reported: Cholestatic jaundice, hepatitis, increased cephalin flocculation and transient liver function test abnormalities (in the absence of jaundice)[Ref]


Very rare (less than 0.01%): Systemic lupus erythematosus

Frequency not reported: Muscular rigidity, altered creatine phosphokinase, acute, distressing muscle spasms in the face, neck, eyes, tongue, and back[Ref]

Acute, distressing muscle spasms usually occurred within 24 hours of injection, and required immediate administration of an anticholinergic agent.[Ref]


Very rare (less than 0.01%): Antinuclear antibodies[Ref]

Nervous system

Parkinsonism/parkinsonian-like states tended to occur 2 to 5 days after each injection, with a decreased frequency in subsequent injections. This side effect may be reduced by using smaller, more frequent doses or adding an anti-parkinsonism agent temporarily.[Ref]

Frequency not reported: Opisthotonos, parkinsonism, pseudoparkinsonism/parkinsonian-like states, dyskinesia, tardive dyskinesia, drowsiness, lethargy, headache, dystonia, acute dystonia/acute dystonic reactions, epileptiform attacks, altered consciousness, stupor, coma, neuroleptic malignant syndrome, autonomic instability, hyperreflexia, akinesia, electroencephalographic tracing alterations, alterations in cerebrospinal fluid proteins, cerebral edema, impairment in judgement and mental skills[Ref]


Frequency not reported: Mild hypotension/hypotension, hypertension, arrhythmias, ventricular tachycardia/fibrillation, venous thromboembolism, deep vein thrombosis, edema, peripheral edema, labile blood pressure, tachycardia, ECG changes, fatal cardiac arrest, QT and T-wave changes[Ref]

ECG changes (including QT and T-wave changes) were dose-related side effects that usually occurred at moderate to high doses. These changes may preclude serious arrhythmias.[Ref]


Frequency not reported: Galactorrhea, abnormal lactation, oligomenorrhea, amenorrhea, menstrual irregularities, impotence, priapism, inhibition of ejaculation (men), increased libido (women), impaired sexual function, bladder paralysis, polyuria, urinary hesitance and/or incontinency[Ref]


Frequency not reported: Abnormal skin pigmentation, skin rashes, diaphoresis/perspiration, itching, erythema multiforme, contact sensitivity, urticaria, seborrhea, photosensitivity, eczema, exfoliative dermatitis, angioneurotic edema[Ref]

Abnormal skin pigmentation occurred in patients receiving high doses for long durations of time.[Ref]


Frequency not reported: Tongue protrusion, dry mouth, constipation, vomiting, nausea, gastric irritation, salivation, fecal impaction, paralytic ileus, difficulty swallowing, aspiration of gastric contents, hypertrophic papillae of the tongue[Ref]


Lens opacities occurred in patients receiving high doses for long durations of time.[Ref]

Frequency not reported: Oculogyric crises, blurred vision, lens opacities, glaucoma, mydriasis, corneal opacity, pigmentation of the eyes, pigmentary retinopathy, defective color vision, night blindness, deposition of particulate matter in the lens and cornea[Ref]


Sudden, unexplained/unexpected death occurred in hospitalized patients with psychosis.[Ref]

Frequency not reported: Neonatal drug withdrawal syndrome

Postmarketing reports: Sudden, unexplained/unexpected deaths, body temperature dysregulation, hypothermia, hyperthermia[Ref]


Frequency not reported: Agitation, restlessness, excitement, insomnia, bizarre dreams, increased aggressiveness, reactivation/aggravation of psychotic processes, catatonic and confusional states[Ref]


Frequency not reported: Nasal congestion, pulmonary embolism, laryngeal dystonia, asthma, throat tightness, difficulty breathing, active fulminating pneumonia or pneumonitis[Ref]


Frequency not reported: Hyperprolactinemia, gynecomastia, false positive pregnancy test, syndrome of inappropriate antidiuretic hormone secretion[Ref]


Frequency not reported: Anaphylactic and hypersensitivity reactions[Ref]


Frequency not reported: Acute renal failure[Ref]


Frequency not reported: Local tissue reactions[Ref]


1. Product Information. Prolixin (fluphenazine). Bristol-Myers Squibb. 2001;PROD.

2. Cerner Multum, Inc. UK Summary of Product Characteristics.

3. Cerner Multum, Inc. Australian Product Information.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.