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    DEA Class;  Rx

    Common Brand Names; Trilafon

    • Antipsychotics, 1st Generation; 
    • Antipsychotics, Phenothiazine
    Oral piperazine phenothiazine antipsychotic agent
    Used primarily as an antipsychotic agent
    Boxed warning regarding increased risk of death in elderly patients with dementia

    Indicated for the treatment of schizophrenia

    For the treatment of severe nausea/vomiting.
    For the treatment of severe behavioral or psychological symptoms of dementia (BPSD).

    Documented hypersensitivity to phenothiazines

    Coma, severe hypotension, severe CNS depression, concurrency with large amounts of CNS depressants, poorly controlled seizure disorder, subcortical brain damage with or without hypothalamic damage, myelosuppression, liver damage, blood dyscrasias

    Severe cardiovascular disease

    Akathisia (60%)


    Decreased gag reflex


    • Akathisia (60%)

    • Dystonia

    • Muscle stiffness

    • Neuroleptic malignant syndrome (infrequent but serious)

    • Parkinsonism

    • Tardive dyskinesia


    • Anticholinergic effects

    • Sedation

    • Weight gain

    • Oligomenorrhea/amenorrhea

    • Erectile dysfunction

    Less Common

    • Orthostatic hypotension (post-IM inj), tachycardia

    • Anxiety, agitation, cerebral edema, depression, dizziness, euphoria, headache, insomnia, restless, weakness

    • Anorexia, dyspepsia, constipation, ileus

    • Lens opacities (prolonged use)


    • ECG changes

    • Photosensitivity

    • Pruritis

    • Galactorrhea

    • Ejaculatory disorder

    • Diarrhea

    • Blood dyscrasia


    • Seizure

    • Priapism

    • Cholestatic jaundice

    Avoid using in children with suspected Reye’s syndrome

    Use caution in prostatic hypertrophy, stenosing PUD, tardive dyskinesia, hypocalcemia, renal/hepatic impairment, patients who have exhibited a severe reaction to insulin or ECT, history of seizures, asthma, respiratory tract infections, cardiovascular disease

    Perphenazine products can lower convulsive threshold in susceptible individuals; they should be used with caution in alcohol withdrawal and in patients with convulsive disorders; if patient is being treated with an anticonvulsant agent, increased dosage of that agent may be required when perphenazine products are used concomitantly

    Should be used with caution in patients with psychiatric depression; possibility of suicide in depressed patients remains during treatment and until significant remission occurs; this type of patient should not have access to large quantities of this drug

    Caution should be observed in giving it to patients who have previously exhibited severe adverse reactions to other phenothiazines some of the untoward actions of perphenazine tend to appear more frequently when high doses are used; patients should be kept under close supervision

    A significant, not otherwise explained, rise in body temperature may suggest individual intolerance to perphenazine, in which case it should be discontinued

    Patients on large doses who are undergoing surgery should be watched carefully for possible hypotensive phenomena; reduced amounts of anesthetics or central nervous system depressants may be necessary

    If abnormalities in hepatic tests occur, phenothiazine treatment should be discontinued

    Pregnancy Category: C

    Lactation: avoid


    24 mg/day PO; dosage may be increased to 64 mg/day PO for short periods.


    24 mg/day PO; dosage may be increased to 64 mg/day PO for short periods.


    24 mg/day PO; dosage may be increased to 64 mg/day PO for short periods.


    12 years: 24 mg/day PO; dosage may be increased to 64 mg/day PO for short periods.
    Less than 12 years: Safety and efficacy have not been established.


    Not indicated.



    • 2mg
    • 4mg
    • 8mg
    • 16mg