Mechanism of effect
Precise mechanism(s) of antipsychotic action not determined, but may be principally related to antidopaminergic effects .
Pharmacodynamic
Exhibits moderate anticholinergic effects , weak to moderate sedative effects , and strong extrapyramidal effects ; possesses strong antiemetic activity.
Pharmacokinetics
• Well absorbed after oral administration appears to undergo substantial first-pass metabolism.
• Peak plasma concentrations generally attained within 1–3 hours.
• Phenothiazines are widely distributed into most body tissues and ffluids. Crosses the placenta . Distributed into breast milk .
• Phenothiazines are highly bound to plasma proteins.
• Extensively metabolized in the liver by sulfoxidation, hydroxylation, dealkylation and glucuronidation .
• Phenothiazines and their metabolites are excreted in urine and feces.Half-life is 9–12 hours following oral administration.
Dosage
Usual Adult Dose for Psychosis
• Moderately disturbed, nonhospitalized patients:
-Recommended dose : 4 to 8 mg orally 3 times a day, with a dose reduction to the minimum effective dose as soon as possible
-Maximum dose : 24 mg/day
• Hospitalized patients :
-Recommended dose: 8 to 16 mg orally 2 to 4 times a day
-Maximum dose: 64 mg/day
Comment :
-Nonhospitalized patients should be limited to a daily dose of 24 mg; maximum doses of 64 mg should be used in hospitalized patients.
Usual Adult Dose for Nausea/Vomiting
• Recommended dose : 8 to 16 mg orally, in divided doses
• Maximum dose: 24 mg/day, in divided doses
• Comment :
-The dose should be reduced as early as possible.
Usual Pediatric Dose for Psychosis
12 years and older :
• Moderately disturbed, nonhospitalized patients:
-Recommended dose : 4 to 8 mg orally 3 times a day, with a dose reduction to the minimum effective dose as soon as possible
-Maximum dose : 24 mg/day
• Hospitalized patients :
-Recommended dose : 8 to 16 mg orally 2 to 4 times a day
-Maximum dose : 64 mg/day
• Comments :
-Nonhospitalized patients should be limited to a daily dose of 24 mg; maximum doses of 64 mg should be used in hospitalized patients.
Usual Pediatric Dose for Nausea/Vomiting
12 years and older :
-Recommended dose: 8 to 16 mg orally, in divided doses
-Maximum dose: 24 mg/day, in divided doses
• Comment :
-The dose should be reduced as early as possible.
Side effects
dry mouth , Blurred vision , Cutaneous Reaction , Weight increase , difficulty urinatingInteractions
Acetylcholine , Epinephrine , Paroxetine , Sertraline , Citalopram , Fluvoxamine , Fluoxetine , escitalopram , lithium , Tretinoin , fentanyl , potassium citrate , Sodium Oxybate , Tapentadol , safinamide , codeine , Apomorphine , Dolasetron , vandetanib , Droperidol , sparfloxacin , Procainamide , Indapamide , Dofetilide , Peginterferon alfa-2b , Lorcaserin , Arsenic trioxide , Halofantrine , Grepafloxacin , aminolevulinic acid oral , Aminolevulinic acid topical , Acetaminophen and benzhydrocodone , Oxymorphone , glycopyrrolate topical , Methyl aminolevulinate , bedaquilineAlerts
• Elderly patients with dementia-related psychosis treated with antipsychotic drugs are at an increased risk of death .
• Perphenazine is not approved for the treatment of patients with dementia-related psychosis .
• A potentially fatal symptom complex, sometimes referred to as Neuroleptic Malignant Syndrome (NMS), has been reported in association with antipsychotic drugs.
• Clinical manifestations of NMS are hyperpyrexia, muscle rigidity, altered mental status and evidence of autonomic instability (irregular pulse or blood pressure, tachycardia, diaphoresis, and cardiac dysrhythmias .
• The management of NMS should include :
1) immediate discontinuation of antipsychotic drugs and other drugs not essential to concurrent therapy,
2) ntensive symptomatic treatment and medical monitoring, and
3) treatment of any concomitant serious medical problems for which specific treatments are available.
• There is no general agreement about specific pharmacological treatment regimens for uncomplicated NMS.
• Perphenazine products are not recommended for pediatric patients under 12 years of age.
• If hypotension develops, epinephrine should not be administered since its action is blocked and partially reversed by Perphenazine. If a vasopressor is needed, norepinephrine may be used.
• Severe, acute hypotension has occurred with the use of phenothiazines and is particularly likely to occur in patients with mitral insufficiency or pheochromocytoma. Rebound hypertension may occur in pheochromocytoma patients.
• Perphenazine products can lower the convulsive threshold in susceptible individuals; they should be used with caution in alcohol withdrawal and in patients with convulsive disorders. If the patient is being treated with an anticonvulsant agent, increased dosage of that agent may be required when Perphenazine products are used concomitantly.
• Perphenazine products should be used with caution in patients with psychic depression.
• Perphenazine may impair the mental and/or physical abilities required for the performance of hazardous tasks such as driving a car or operating machinery; therefore, the patient should be warned accordingly.
• In clinical trial and postmarketing experience, events of leukopenia/ neutropenia and agranulocytosis have been reported temporally related to antipsychotic agents.
Points of recommendation
To make sure this medicine is safe for you, tell your doctor if you have :
• If you have an allergy to perphenazine or any other part of perphenazine.
• If you are allergic to any drugs like this one, any other drugs, foods, or other substances. Tell your doctor about the allergy and what signs you had, like rash; hives; itching; shortness of breath; wheezing; cough; swelling of face, lips, tongue, or throat; or any other signs.
• If you have any of these health problems: Blood problems, bone marrow disease, brain problems, liver disease, or low blood cell count.
• If you are very sleepy.
• If you have recently drunk a lot of alcohol or taken a big amount of drugs that may slow your actions like phenobarbital or some pain drugs like oxycodone.
• If your child is younger than 12 years of age. Do not give this medicine to a child younger than 12 years of age.
A very bad and sometimes deadly health problem called neuroleptic malignant syndrome (NMS) may happen.
- Call your doctor right away if you have any fever, muscle cramps or stiffness, dizziness, very bad headache, confusion, change in thinking, fast heartbeat, heartbeat that does not feel normal, or are sweating a lot.
- Take with or without food. Take with food if it causes an upset stomach.
- Take a missed dose as soon as you think about it. If it is close to the time for your next dose, skip the missed dose and go back to your normal time.
- Do not take 2 doses at the same time or extra doses.
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