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.

This medication may be available under multiple brand names and/or in several different forms. Any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of this medication may not be used for all of the conditions discussed here.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. 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?

Apo-Fluphenazine is no longer being manufactured for sale in Canada. For brands that may still be available, search under fluphenazine. This article is being kept available for reference purposes only. If you are using this medication, speak with your doctor or pharmacist for information about your treatment options.

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.

The recommended starting dose for seniors is 1 mg to 2.5 mg taken daily.

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 brain damage or blockage of the blood vessels in the brain
  • have severe kidney disease
  • have a tumour known as pheochromocytoma
  • have severe heart disease
  • have or have had brain damage
  • have drowsiness, decreased alertness, or slowed breathing, possibly due to any of the following:
    • alcohol consumption
    • medications that cause sedation (e.g., sedatives, narcotic pain relievers, certain antidepressants)
    • certain blood disorders (i.e., bone marrow suppression or blood dyscrasias)
    • severe liver disease
  • are going to receive anesthesia (spinal or general anesthesia)

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
  • appetite changes
  • bizarre dreams
  • blurred vision
  • constipation
  • change in interest for sexual activity
  • decreased sexual ability
  • difficulty adjusting to extreme temperatures
  • difficulty coordinating muscles
  • difficulty sleeping
  • difficulty urinating
  • dizziness
  • drowsiness
  • dry eyes
  • dry mouth
  • excitement
  • headache
  • hormonal changes (e.g., enlarged breasts, breast pain, menstrual changes, sexual dysfunction)
  • increased salivation
  • increased urination
  • nasal congestion
  • nausea
  • rashes
  • reduced blood pressure (lightheadedness or dizziness when rising from a sitting or lying position)
  • sedation
  • sensitivity to light
  • sweating
  • vomiting
  • weight change

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:

  • breast enlargement in men
  • confusion
  • decreased bladder control
  • increased blood pressure (e.g., headache, nausea, vomiting, vision changes)
  • involuntary muscle movements, twitching, or tremors (e.g., tongue, face, mouth or jaw)
  • loss of balance control
  • mask-like face
  • movement disorders (e.g., continuous muscle spasms and contractions; slow movements; irregular, jerky movements; tremor; inability to move eyes; increased blinking; puffing of cheeks; muscle stiffness; shuffling walk)
  • severe restlessness or need to keep moving
  • signs of a blood clot in the arm or leg (tenderness, pain, swelling, warmth, or redness in the arm or leg) or lungs (difficulty breathing, sharp chest pain that is worse when breathing in, coughing, coughing up blood, sweating, or passing out)
  • signs of liver problems (e.g., nausea, vomiting, diarrhea, loss of appetite, weight loss, yellowing of the skin or whites of the eyes, dark urine, pale stools)
  • symptoms of anemia (low red blood cells; e.g., dizziness, pale skin, unusual tiredness or weakness, shortness of breath)
  • symptoms of high blood sugar (e.g., frequent urination, increased thirst, excessive eating, unexplained weight loss, poor wound healing, infections, fruity breath odour)
  • symptoms of a lung infection (e.g., fever, flu-like symptoms, coughing, trouble breathing)
  • vision changes (e.g., blurred vision, change in colour vision, or difficulty in seeing at night)

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

  • difficult or fast breathing
  • extrapyramidal symptoms (e.g., continuous muscle spasms and contractions, slow movements, irregular, jerky movements, tremor)
  • fast or irregular heartbeat
  • hallucinations
  • long-lasting (greater than 4 hours) and painful erection of the penis
  • new or worsening constipation
  • seizures
  • signs of a severe allergic reaction (such as difficulty breathing; skin rash or hives; swelling of the lips, mouth, or throat)
  • signs of neuroleptic malignant syndrome (e.g., confusion, reduced consciousness, high fever, or muscle stiffness)
  • signs of stroke (e.g., sudden or severe headache; sudden loss of coordination; vision changes; sudden slurring of speech; or unexplained weakness, numbness, or pain in arm or leg)
  • symptoms of brain swelling (e.g., severe headache, slow heart rate, irritability, weakness, difficulty talking, drowsiness, fainting, vomiting)
  • trembling or shaking
  • trouble in speaking or swallowing
  • worsening behavioural symptoms

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 withdrawal: 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.

Alcohol and other medications that cause drowsiness: People taking this medication should not combine it with alcohol, and should avoid combining it with other medications, such as narcotic pain relievers or sedatives, that cause drowsiness. Doing so can cause additive drowsiness and reduced breathing, as well as other side effects, which can be dangerous and possibly life-threatening.

Blood clots: This medication may increase the chance of blood clot formation. If you have a history of clotting you may be at increased risk of experiencing blood clot-related problems such as heart attack, stroke, or clots in the deep veins of your leg. If you experience symptoms such as sharp pain and swelling in the leg, difficulty breathing, chest pain, blurred vision or difficulty speaking, contact your doctor immediately.

Blood counts: This medication can decrease the number of neutrophils (a type of white blood cell that helps fight infection), red blood cells (which carry oxygen), and platelets (which help your blood to clot). Your doctor will periodically order blood tests to monitor this. If you notice any signs of infection (e.g., fever, chills, or sore throat) or unusual bleeding or bruising, contact your doctor immediately.

Body temperature: Fluphenazine, like other antipsychotic medications, may interfere with your body's ability to regulate body temperature in extreme hot or cold conditions. People who exercise vigorously, who are exposed to extreme heat, are dehydrated, or are taking anticholinergic medications (e.g., benztropine, oxybutynin) are more at risk. Contact your doctor as soon as possible if you feel very hot and are unable to cool down.

Take care to avoid overheating during strenuous exercise or in hot temperatures, and avoid becoming dehydrated by drinking enough fluids.

Constipation: Fluphenazine may cause the passage of material through the digestive system to slow down or stop. Rarely, and particularly with seniors, muscles in the digestive system stop working together. This condition can become a medical emergency if it is not corrected early. If you experience constipation, talk to your doctor.

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.

Heart rhythm: Fluphenazine can cause changes to the normal rhythm of the heart, including an irregular heartbeat called QT prolongation. QT prolongation is a serious life-threatening condition that can cause fainting, seizures, and sudden death. If you are at risk for heart rhythm problems (e.g., people with heart failure, angina, low potassium or magnesium levels), 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.

Low blood pressure: Some people taking fluphenazine may experience sudden blood pressure drops when getting up from a sitting or lying position. These blood pressure drops could lead to dizziness, lightheadedness, and falls, especially for seniors taking this medication. If you experience this problem, try getting up more slowly. If it persists or if you faint, contact your doctor.

Neuroleptic malignant syndrome (NMS):Fluphenazine, like other antipsychotic medications, can cause a potentially fatal syndrome known as neuroleptic malignant syndrome(NMS). If you notice the symptoms of NMS such as high fever, muscle stiffness, confusion or loss of consciousness, sweating, racing or irregular heartbeat, or fainting, get immediate medical attention.

Seizures: Like other similar medications, fluphenazine may cause seizures. If you have a history of epilepsy or medical conditions that increase the risk of seizures, 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.

Tardive Dyskinesia (TD): Like some other antipsychotic medications, fluphenazine may cause tardive dyskinesia (TD) to develop. TD is a potentially irreversible syndrome of involuntary, repetitive movements of the face and tongue muscles. Although TD appears most commonly in seniors, especially women, it is impossible to predict who will develop TD. The risk of developing TD increases with higher doses and long-term treatment. If you experience muscle twitching or abnormal movements of the face or tongue, contact your doctor as soon as possible.

Vision Changes: This medication may cause vision changes. While you are taking fluphenazine, regular eye examinations should occur, to identify early changes to the eyes.

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 and adolescents less than 18 years of age.

Seniors: Seniors should use this medication with caution. Similar medications to fluphenazine have been associated with an increased risk of death due to stroke and heart attack when used in elderly people with dementia.This medication should not be used in people over the age of 60 years who have dementia.

What other drugs could interact with this medication?

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

  • aclidinium
  • alcohol
  • amphetamines (e.g., dextroamphetamine, lisdexamfetamine)
  • antacids (e.g., aluminum hydroxide, calcium carbonate, magnesium hydroxide)
  • antiarrhythmics (e.g., amiodarone, dronedarone, disopyramide, quinidine)
  • antihistamines (e.g., cetirizine, doxylamine, diphenhydramine, hydroxyzine, loratadine)
  • anti-Parkinsons medications (e.g., amantadine, apomorphine, bromocriptine, levodopa, pramipexole, ropinirole)
  • atropine
  • barbiturates (e.g., butalbital, phenobarbital)
  • benzodiazepines (e.g., alprazolam, diazepam, lorazepam)
  • benztropine
  • beta-adrenergic blockers (e.g., atenolol, propranolol, sotalol)
  • brimonidine
  • buprenorphine
  • bupropion
  • buspirone
  • butorphanol
  • cabergoline
  • caffeine
  • cannabis
  • chloral hydrate
  • clidinium
  • clonidine
  • dantrolene
  • darifenacin
  • dexmethylphenidate
  • dimenhydrinate
  • diphenoxylate
  • disulfiram
  • domperidone
  • donepezil
  • efavirenz
  • eluxadoline
  • epinephrine
  • esketamine
  • fesoterodine
  • flibanserin
  • galantamine
  • general anesthetics (medications used to put people to sleep before surgery)
  • glucagon
  • glycopyrrolate
  • guanfacine
  • ipratropium
  • ketotifen
  • lemborexant
  • linezolid
  • lithium
  • methadone
  • methotrimeprazine
  • methylphenidate
  • metoclopramide
  • mirabegron
  • mirtazapine
  • monoamine oxidase inhibitors (MAOIs; e.g., moclobemide, rasagiline, selegiline, tranylcypromine)
  • muscle relaxants (e.g., baclofen, cyclobenzaprine, methocarbamol, orphenadrine)
  • nabilone
  • narcotic pain relievers (e.g., codeine, fentanyl, morphine, oxycodone, tapentadol, tramadol)
  • nitroglycerin
  • other antipsychotics (e.g., chlorpromazine, clozapine, haloperidol, olanzapine, quetiapine, risperidone)
  • oxybutynin
  • pizotifen
  • pomalidomide
  • potassium chloride
  • pregabalin
  • pseudoephedrine
  • rivastigmine
  • St. John's wort
  • Saquinavir
  • scopolamine
  • seizure medications (e.g., carbamazepine, clobazam, levetiracetam, phenobarbital, phenytoin, primidone, topiramate, valproic acid,)
  • selective serotonin reuptake inhibitors (SSRIs; e.g., citalopram, fluoxetine, paroxetine, sertraline)
  • serotonin/norepinephrine reuptake inhibitors (SNRIs; e.g., desvenlafaxine, duloxetine, venlafaxine)
  • sodium oxybate
  • solifenacin
  • tetrabenazine
  • theophyllines (e.g., aminophylline, theophylline)
  • thiazide diuretics (water pills; e.g., hydrochlorothiazide, indapamide, metolazone)
  • tiotropium
  • tizanidine
  • tolterodine
  • trazodone
  • tricyclic antidepressants (e.g., clomipramine, desipramine, imipramine)
  • trospium
  • tryptophan
  • umeclidinium
  • valerian
  • vandetanib
  • zolpidem
  • zopiclone

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.

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