How does this medication work? What will it do for me?

This medication is used to manage psychotic disorders such as agitated depression and schizophrenia. It also is used as a tranquilizer to help reduce agitated and disruptive behaviour and to manage severe nausea and vomiting. It works by affecting the balance of certain chemicals in the brain.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. As well, some forms of this medication may not be used for all of the conditions discussed here. If you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. Do not stop taking this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.

What form(s) does this medication come in?

2 mg
Each round, white, biconvex, film-coated tablet, identified "2", contains perphenazine 2 mg. Nonmedicinal ingredients: carnauba wax, cornstarch, hydroxypropyl methylcellulose, lactose monohydrate, magnesium stearate, microcrystalline cellulose, polyethylene glycol 3350 (carbowax), and titanium dioxide.

4 mg
Each round, white, biconvex, film-coated tablet, identified "4", contains perphenazine 4 mg. Nonmedicinal ingredients: carnauba wax, cornstarch, hydroxypropyl methylcellulose, lactose monohydrate, magnesium stearate, microcrystalline cellulose, polyethylene glycol 3350 (carbowax), and titanium dioxide.

8 mg
Each round, white, biconvex, film-coated tablet, identified "8", contains perphenazine 8 mg. Nonmedicinal ingredients: carnauba wax, cornstarch, hydroxypropyl methylcellulose, lactose monohydrate, magnesium stearate, microcrystalline cellulose, polyethylene glycol 3350 (carbowax), and titanium dioxide.

16 mg
Each round, white, biconvex, film-coated tablet, identified "16", contains perphenazine 16 mg. Nonmedicinal ingredients: carnauba wax, cornstarch, hydroxypropyl methylcellulose, lactose monohydrate, magnesium stearate, microcrystalline cellulose, polyethylene glycol 3350 (carbowax), and titanium dioxide.

How should I use this medication?

The recommended dose varies widely up to a maximum of 24 mg daily, depending on the condition being treated and the circumstances.

Many things can affect the dose of a medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are taking the medication without consulting your doctor.

Do not dispose of medications in wastewater (e.g. down the sink or in the toilet) or in household garbage. Ask your pharmacist how to dispose of medications that are no longer needed or have expired.

Who should NOT take this medication?

Perphenazine should not be taken by anyone who:

  • is allergic to perphenazine or to any of the ingredients of the medication
  • is comatose or non-functional
  • is receiving large doses of central nervous system depressants (e.g., barbiturates, alcohol, analgesics, or antihistamines)
  • has abnormal blood function
  • has bone marrow depression
  • has liver damage
  • has or may have subcortical brain damage

What side effects are possible with this medication?

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent. The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

  • blurred vision
  • changes in menstrual cycles
  • constipation
  • dizziness upon rising from a sitting or lying down position
  • drowsiness (usually during the first 2 weeks)
  • dry mouth
  • impaired urination
  • nasal congestion

A significant rise in body temperature, not otherwise explained, may suggest intolerance to perphenazine, in which case use of the medication should be discontinued.

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

Are there any other precautions or warnings for this medication?

Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.

Drowsiness/reduced alertness: Perphenazine may impair the mental or physical abilities required to perform certain tasks, such as driving a car or operating machinery.

Seizures: Perphenazine can lower the seizure threshold in certain people. People in alcohol withdrawal or with seizure disorders should be monitored by their doctor.

Sun: People being treated with phenothiazines such as perphenazine should avoid undue exposure to sunlight.

Tardive dyskinesia: Tardive dyskinesia is characterized by involuntary movements that may develop in people treated with antipsychotic medications such as perphenazine. Although this seems to be most frequent among the elderly, especially elderly women, this cannot be used to predict who will develop this syndrome. Both the risk of developing tardive dyskinesia and the likelihood that it will become irreversible are believed to increase as the length of treatment and the total dose of perphenazine increases. If signs and symptoms of tardive dyskinesia appear, speak to your doctor about stopping the medication. However, some people may require treatment despite the presence of the syndrome.

Pregnancy: This medication should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking this medication, contact your doctor.

Breast-feeding: Perphenazine is excreted rapidly in breast milk and could cause serious side effects in the breast-fed infant. Breast-feeding mothers should make a decision with their doctor whether to stop taking the medication or stop breast-feeding.

Children: The safety and effectiveness of perphenazine have not been established for use by children under 12 years of age.

What other drugs could interact with this medication?

There may be an interaction between perphenazine and any of the following:

  • alcohol

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

  • stop taking one of the medications,
  • change one of the medications to another,
  • change how you are taking one or both of the medications, or
  • leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.