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

Fluphenazine belongs to the family of medications known as phenothiazines. It is thought to work by the effect it has on nerve pathways in certain areas of the brain. This medication is used to treat mental and emotional conditions.

Your doctor may have suggested this medication for conditions other than the ones 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?

This medication is available as 1 mg, 2 mg, 2.5 mg, and 5 mg tablets.

How should I use this medication?

The recommended dose of this medication varies widely depending on the condition being treated. The usual starting dose ranges from 2.5 mg to 10 mg daily in divided doses every 6 to 8 hours. The smallest amount of medication that will produce the desired effect is the dose your doctor will eventually prescribe. The usual maintenance dose ranges from 1 mg to 5 mg daily as a single dose.

You may take this medication with food or milk if stomach upset occurs, unless your doctor tells you otherwise.

Do not stop taking fluphenazine suddenly without talking to your doctor. Some conditions may worsen if the medication is suddenly stopped.

It may take up to 2 weeks for the full benefit of this medication to take effect.

Many things can affect the dose of 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.

It is important to take this medication exactly as prescribed by your doctor. If you miss a dose, take it as soon as possible and continue with your regular schedule. If it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.

Store this medication at room temperature and protect it from light.

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?

Do not take fluphenazine if you:

  • are allergic to fluphenazine or any ingredients of the medication
  • have certain blood disorders (i.e. bone marrow suppression or blood dyscrasias)
  • have severe liver disease
  • have severely depressed mental function or coma

There may be other conditions where your doctor may not want you to use this medication. Be sure to tell all health professionals involved in your care of all your medical conditions.

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 2% 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.

  • agitation
  • blurred vision
  • constipation
  • change in blood sugars
  • difficulty adjusting to extreme temperatures
  • difficulty coordinating muscles
  • difficulty sleeping
  • difficulty urinating
  • dry eyes
  • dry mouth
  • hormonal changes (e.g. enlarged breasts, breast pain, menstrual changes, sexual dysfunction)
  • increased heart rate
  • increased urination
  • involuntary muscle movements, twitching, or tremors (e.g. tongue, face, mouth, or jaw)
  • reduced blood pressure
  • sedation
  • sensitivity to light
  • weight gain

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

  • blurred vision, change in colour vision, or difficulty in seeing at night
  • fainting
  • fever
  • involuntary muscle movements, twitching, or tremors (e.g. tongue, face, mouth or jaw)
  • loss of balance control
  • mask-like face
  • muscle rigidity
  • puffing of cheeks
  • severe restlessness or need to keep moving
  • shuffling walk
  • stiffness of arms and legs
  • trembling and shaking of fingers and hands
  • severe sunburn
  • skin rash

Stop taking this medication and seek immediate medical attention if any of the following occur:

  • difficult or fast breathing
  • fast heartbeat
  • fever
  • increased sweating
  • loss of bladder control
  • severe change in blood pressure
  • severe confusion or coma
  • severe muscle stiffness
  • signs of a severe allergic reaction (such as difficulty breathing; skin rash or hives; swelling of the lips, mouth, or throat)
  • trembling or shaking
  • trouble in speaking or swallowing

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 taking 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 take this medication.

Abrupt withrawal: Stopping this medication suddenly can result in symptoms including nausea, vomiting, diarrhea, sweating, insomnia and confusion. This medication should be discontinued gradually and under medical direction.

Drowsiness/reduced alertness: The use of this medication may impair the mental and physical abilities required for driving a car or operating machinery. Avoid consuming alcohol while on this medication as it can produce extreme drowsiness.

Medical conditions: If you have a history of seizures, hypocalcemia, respiratory difficulties, or liver disease, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Sun: This medication makes you more sensitive to the harmful effects of sunlight. Make sure to apply a broad spectrum sunscreen prior to sunlight exposure.

Temperature control: This medication reduces your ability to adapt to extreme temperatures. Avoid extreme heat or cold.

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 immediately.

Breast-feeding: Fluphenazine passes into breast milk. If you are a breast-feeding mother and are taking this medication, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

Children: The safety and effectiveness of using this medication have not been established for children under 12 years of age.

Seniors: Seniors should use this medication with caution, and should not exceed the recommended dose. Your doctor may prescribe a lower dose due to greater risk for side effects.

What other drugs could interact with this medication?

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

  • alcohol
  • anticonvulsants (e.g. valproic acid, phenytoin)
  • antidepressants (e.g. fluoxetine, paroxetine, amitriptyline)
  • atropine
  • barbiturates (e.g. phenobarbital)
  • benzodiazepines (e.g. lorazepam, temazepam)
  • drowsiness-causing antihistamines (e.g. diphenhydramine, dimenhydrinate)
  • lithium
  • medications for Parkinson’s disease (e.g. benztropine, levodopa, pramipexole)
  • quinidine
  • ritonavir

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.