Perphenazine

INDICATIONS AND USAGE Perphenazine is indicated for use in the treatment of schizophrenia and for the control of severe nausea and vomiting in adults. Perphenazine has not been shown effective for the management of behavioral complications in patients with mental retardation.

DOSAGE AND ADMINISTRATION Dosage must be individualized and adjusted according to the severity of the condition and the response obtained. As with all potent drugs, the best dose is the lowest dose that will produce the desired clinical effect. Since extrapyramidal symptoms increase in frequency and severity with increased dosage, it is important to employ the lowest effective dose. These symptoms have disappeared upon reduction of dosage, withdrawal of the drug, or administration of an antiparkinsonian agent. Prolonged administration of doses exceeding 24 mg daily should be reserved for hospitalized patients or patients under continued observation for early detection and management of adverse reactions. An antiparkinsonian agent, such as trihexyphenidyl hydrochloride or benztropine mesylate, is valuable in controlling drug-induced extrapyramidal symptoms. Suggested dosages for various conditions follow: Moderately disturbed nonhospitalized patients with schizophrenia 4 to 8 mg three times a day initially; reduce as soon as possible to minimum effective dosage. Hospitalized patients with schizophrenia 8 to 16 mg two times a day to four times a day; avoid dosages in excess of 64 mg daily. Severe nausea and vomiting in adults 8 to 16 mg daily in divided doses; 24 mg occasionally may be necessary; early dosage reduction is desirable. Elderly Patients With increasing age, plasma concentrations of perphenazine per daily ingested dose increase. Geriatric dosages of perphenazine preparations have not been established, but initiation of lower dosages is recommended. Optimal clinical effect or benefit may require lower doses for a longer duration. Dosing of perphenazine may occur before bedtime, if required.

CONTRAINDICATIONS Perphenazine products are contraindicated in comatose or greatly obtunded patients and in patients receiving large doses of central nervous system depressants (barbiturates, alcohol, narcotics, analgesics, or antihistamines); in the presence of existing blood dyscrasias, bone marrow depression, or liver damage; and in patients who have shown hypersensitivity to perphenazine products, their components, or related compounds. Perphenazine products are also contraindicated in patients with suspected or established subcortical brain damage, with or without hypothalamic damage, since a hyperthermic reaction with temperatures in excess of 104°F may occur in such patients, sometimes not until 14 to 16 hours after drug administration. Total body ice-packing is recommended for such a reaction; antipyretics may also be useful.

ADVERSE REACTIONS Not all of the following adverse reactions have been reported with this specific drug; however, pharmacological similarities among various phenothiazine derivatives require that each be considered. With the piperazine group (of which perphenazine is an example), the extrapyramidal symptoms are more common, and others (e.g., sedative effects, jaundice, and blood dyscrasias) are less frequently seen. CNS Effects Extrapyramidal Reactions opisthotonus, trismus, torticollis, retrocollis, aching and numbness of the limbs, motor restlessness, oculogyric crisis, hyperreflexia, dystonia, including protrusion, discoloration, aching and rounding of the tongue, tonic spasm of the masticatory muscles, tight feeling in the throat, slurred speech, dysphagia, akathisia, dyskinesia, parkinsonism, and ataxia. Their incidence and severity usually increase with an increase in dosage, but there is considerable individual variation in the tendency to develop such symptoms. Extrapyramidal symptoms can usually be controlled by the concomitant use of effective antiparkinsonian drugs, such as benztropine mesylate, and/or by reduction in dosage. In some instances, however, these extrapyramidal reactions may persist after discontinuation of treatment with perphenazine. Dystonia Class effect : Symptoms of dystonia, prolonged abnormal contractions of muscle groups, may occur in susceptible individuals during the first few days of treatment. Dystonic symptoms include: spasm of the neck muscles, sometimes progressing to tightness of the throat, swallowing difficulty, difficulty breathing, and/or protrusion of the tongue. While these symptoms can occur at low doses, they occur more frequently and with greater severity with high potency and at higher doses of first generation antipsychotic drugs. An elevated risk of acute dystonia is observed in males and younger age groups. Persistent Tardive Dyskinesia As with all antipsychotic agents, tardive dyskinesia may appear in some patients on long-term therapy or may appear after drug therapy has been discontinued. Although the risk appears to be greater in elderly patients on high-dose therapy, especially females, it may occur in either sex and in children. The symptoms are persistent and in some patients appear to be irreversible. The syndrome is characterized by rhythmical, involuntary movements of the tongue, face, mouth or jaw (e.g., protrusion of tongue, puffing of cheeks, puckering of mouth, chewing movements). Sometimes these may be accompanied by involuntary movements of the extremities. There is no known effective treatment for tardive dyskinesia; antiparkinsonism agents usually do not alleviate the symptoms of this syndrome. It is suggested that all antipsychotic agents be discontinued if these symptoms appear. Should it be necessary to reinstitute treatment, or increase the dosage of the agent, or switch to a different antipsychotic agent, the syndrome may be masked. It has been reported that fine, vermicular movements of the tongue may be an early sign of the syndrome, and if the medication is stopped at that time the syndrome may not develop. Other CNS Effects Include cerebral edema; abnormality of cerebrospinal fluid proteins; convulsive seizures, particularly in patients with EEG abnormalities or a history of such disorders; and headaches. Neuroleptic malignant syndrome has been reported in patients treated with antipsychotic drugs (see WARNINGS ). Drowsiness may occur, particularly during the first or second week, after which it generally disappears. If troublesome, lower the dosage. Hypnotic effects appear to be minimal, especially in patients who are permitted to remain active. Adverse behavioral effects include paradoxical exacerbation of psychotic symptoms, catatonic-like states, paranoid reactions, lethargy, paradoxical excitement, restlessness, hyperactivity, nocturnal confusion, bizarre dreams, and insomnia. Hyperreflexia has been reported in the newborn when a phenothiazine …

Drug Interactions Metabolism of a number of medications, including antipsychotics, antidepressants, ß-blockers, and antiarrhythmics, occurs through the cytochrome P450 2D6 isoenzyme (debrisoquine hydroxylase). Approximately 10% of the Caucasian population has reduced activity of this enzyme, so-called “poor” metabolizers. Among other populations the prevalence is not known. Poor metabolizers demonstrate higher plasma concentrations of antipsychotic drugs at usual doses, which may correlate with emergence of side effects. In one study of 45 elderly patients suffering from dementia treated with perphenazine, the 5 patients who were prospectively identified as poor P450 2D6 metabolizers had reported significantly greater side effects during the first 10 days of treatment than the 40 extensive metabolizers, following which the groups tended to converge. Prospective phenotyping of elderly patients prior to antipsychotic treatment may identify those at risk for adverse events. The concomitant administration of other drugs that inhibit the activity of P450 2D6 may acutely increase plasma concentrations of antipsychotics. Among these are tricyclic antidepressants and selective serotonin reuptake inhibitors, e.g., fluoxetine, sertraline and paroxetine. When prescribing these drugs to patients already receiving antipsychotic therapy, close monitoring is essential and dose reduction may become necessary to avoid toxicity. Lower doses than usually prescribed for either the antipsychotic or the other drug may be required.

ACTIONS Perphenazine has actions at all levels of the central nervous system, particularly the hypothalamus. However, the site and mechanism of action of therapeutic effect are not known.

DESCRIPTION Perphenazine (4-[3-(2-chlorophenothiazin-10-yl) propyl]-1-piperazineethanol), a piperazinyl phenothiazine, having the chemical formula, C 21 H 26 CIN 3 OS. It is available as oral tablets containing 2 mg, 4 mg, 8 mg, and 16 mg of perphenazine. Inactive ingredients: lactose (monohydrate), hypromellose, magnesium stearate, microcrystalline cellulose, polyethylene glycol, starch (corn), talc, titanium dioxide, and polysorbate 80. Its structural formula is: Chemical Structure ACTIONS Perphenazine has actions at all levels of the central nervous system, particularly the hypothalamus. However, the site and mechanism of action of therapeutic effect are not known.

OVERDOSAGE In the event of overdosage, emergency treatment should be started immediately. Consultation with a poison center should be considered. All patients suspected of having taken an overdose should be hospitalized as soon as possible. Manifestations The toxic effects of perphenazine are typically mild to moderate with death occurring in cases involving a large overdose. Overdosage of perphenazine primarily involves the extrapyramidal mechanism and produces the same side effects described under ADVERSE REACTIONS , but to a more marked degree. It is usually evidenced by stupor or coma; children may have convulsive seizures. Signs of arousal may not occur for 48 hours. The primary effects of medical concern are cardiac in origin including tachycardia, prolongation of the QRS or QTc intervals, atrioventricular block, torsade de pointes, ventricular dysrhythmia, hypotension or cardiac arrest, which indicate serious poisoning. Deaths by deliberate or accidental overdosage have occurred with this class of drugs. Treatment Treatment is symptomatic and supportive. Induction of emesis is not recommended because of the possibility of a seizure, CNS depression, or dystonic reaction of the head or neck and subsequent aspiration. Gastric lavage (after intubation, if the patient is unconscious) and administration of activated charcoal together with a laxative should be considered. There is no specific antidote. Standard measures (oxygen, intravenous fluids, corticosteroids) should be used to manage circulatory shock or metabolic acidosis. An open airway and adequate fluid intake should be maintained. Body temperature should be regulated. Hypothermia is expected, but severe hyperthermia may occur and must be treated vigorously (see CONTRAINDICATIONS ). An electrocardiogram should be taken and close monitoring of cardiac function instituted if there is any sign of abnormality. Close monitoring of cardiac function is advisable for not less than five days. Vasopressors such as norepinephrine may be used to treat hypotension, but epinephrine should NOT be used. Hemodialysis and peritoneal dialysis are of no value because of low plasma concentrations of the drug. Since overdosage is often deliberate, patients may attempt suicide by other means during the recovery phase.

Manifestations The toxic effects of perphenazine are typically mild to moderate with death occurring in cases involving a large overdose. Overdosage of perphenazine primarily involves the extrapyramidal mechanism and produces the same side effects described under ADVERSE REACTIONS , but to a more marked degree. It is usually evidenced by stupor or coma; children may have convulsive seizures. Signs of arousal may not occur for 48 hours. The primary effects of medical concern are cardiac in origin including tachycardia, prolongation of the QRS or QTc intervals, atrioventricular block, torsade de pointes, ventricular dysrhythmia, hypotension or cardiac arrest, which indicate serious poisoning. Deaths by deliberate or accidental overdosage have occurred with this class of drugs.

Treatment Treatment is symptomatic and supportive. Induction of emesis is not recommended because of the possibility of a seizure, CNS depression, or dystonic reaction of the head or neck and subsequent aspiration. Gastric lavage (after intubation, if the patient is unconscious) and administration of activated charcoal together with a laxative should be considered. There is no specific antidote. Standard measures (oxygen, intravenous fluids, corticosteroids) should be used to manage circulatory shock or metabolic acidosis. An open airway and adequate fluid intake should be maintained. Body temperature should be regulated. Hypothermia is expected, but severe hyperthermia may occur and must be treated vigorously (see CONTRAINDICATIONS ). An electrocardiogram should be taken and close monitoring of cardiac function instituted if there is any sign of abnormality. Close monitoring of cardiac function is advi …

HOW SUPPLIED Perphenazine tablets, USP are available as: 2 mg: White film coated, round, biconvex tablets debossed “701” on one side and plain on the other side, supplied as: NDC 71205-841-30 bottles of 30 tablets NDC 71205-841-60 bottles of 60 tablets NDC 71205-841-90 bottles of 90 tablets NDC 71205-841-00 bottles of 100 tablets NDC 71205-841-72 bottles of 120 tablets NDC 71205-841-78 bottles of 180 tablets NDC 71205-841-64 bottles of 240 tablets NDC 71205-841-55 bottles of 500 tablets NDC 71205-841-11 bottles of 1000 tablets 4 mg: White film coated, round, biconvex tablets debossed “702” on one side and plain on the other side, supplied as: NDC 71205-842-30 bottles of 30 tablets NDC 71205-842-60 bottles of 60 tablets NDC 71205-842-90 bottles of 90 tablets NDC 71205-842-00 bottles of 100 tablets NDC 71205-842-72 bottles of 120 tablets NDC 71205-842-78 bottles of 180 tablets NDC 71205-842-64 bottles of 240 tablets NDC 71205-842-55 bottles of 500 tablets NDC 71205-842-11 bottles of 1000 tablets 8 mg: White film coated, round, biconvex tablets debossed “704” on one side and plain on the other side, supplied as: NDC 71205-843-30 bottles of 30 tablets NDC 71205-843-60 bottles of 60 tablets NDC 71205-843-90 bottles of 90 tablets NDC 71205-843-00 bottles of 100 tablets NDC 71205-843-72 bottles of 120 tablets NDC 71205-843-78 bottles of 180 tablets NDC 71205-843-64 bottles of 240 tablets NDC 71205-843-55 bottles of 500 tablets NDC 71205-843-11 bottles of 1000 tablets 16 mg: White film coated, round, biconvex tablets debossed “705” on one side and plain on the other side, supplied as: NDC 71205-844-30 bottles of 30 tablets NDC 71205-844-60 bottles of 60 tablets NDC 71205-844-90 bottles of 90 tablets NDC 71205-844-00 bottles of 100 tablets NDC 71205-844-72 bottles of 120 tablets NDC 71205-844-78 bottles of 180 tablets NDC 71205-844-64 bottles of 240 tablets NDC 71205-844-55 bottles of 500 tablets NDC 71205-844-11 bottles of 1000 tablets Store at 20° to 25°C (68° to 77°F) [See USP Controlled Room Temperature]. Dispense in a tight, light-resistant container. Manufactured by: Ingenus Pharmaceuticals NJ, LLC Fairfield, NJ 07004 Distributed by: Rising Pharmaceuticals, Inc. Saddle Brook, NJ 07663 Repackaged and Relabeled by: Proficient Rx LP Thousand Oaks, CA 91320 Rev. 03/2019