Fluphenazine is a typical antipsychotic and is used to treat conditions that cause psychosis. It's available as short-acting fluphenazine hydrochloride (tablets, liquid, injection) that's typically taken by mouth or injected 3 to 4 times a day. It also comes as long-acting fluphenazine decanoate (injection) that's usually given every 4 to 6 weeks. Side effects of this medication include drowsiness and movement problems. Brand name Prolixin is no longer available.
Psychotic disorders
Fluphenazine is a typical antipsychotic. It works by blocking dopamine activity in your brain, which affects your thoughts and mood.
Source: DailyMed
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Phenothiazines can sometimes cause serious unwanted effects. Tardive dyskinesia or tardive dystonia (muscle movement disorders) may occur and may not go away after you stop using the medicine. Signs of tardive dyskinesia or tardive dystonia include worm-like movements of the tongue, or other uncontrolled movements of the mouth, tongue, cheeks, jaw, body, arms, or legs. Another possible serious unwanted effect is the neuroleptic malignant syndrome (NMS). Signs and symptoms of NMS include severe muscle stiffness, fever, fast heartbeat, difficult breathing, increased sweating, and loss of bladder control. You and your doctor should discuss the good this medicine will do as well as the risks of taking it.
Stop taking this medicine and get emergency help immediately if any of the following effects occur:
Rare
Symptoms of neuroleptic malignant syndrome
Confusion (severe) or coma
difficult or fast breathing
fast heartbeat
high or low (irregular) blood pressure
increased sweating
loss of bladder control
muscle stiffness (severe)
trembling or shaking
trouble in speaking or swallowing
Check with your doctor immediately if any of the following side effects occur:
More common
Inability to move eyes
increased blinking or spasms of eyelid
lip smacking or puckering
muscle spasms of face, neck, body, arms, or legs causing unusual postures or unusual expressions on face
puffing of cheeks
rapid or worm-like movements of tongue
sticking out of tongue
tic-like or twitching movements
trouble in breathing, speaking, or swallowing
uncontrolled chewing movements
uncontrolled movements of arms or legs
uncontrolled twisting movements of neck, trunk, arms, or leg
Rare
Irregular or slow heart rate
recurrent fainting
Check with your doctor as soon as possible if any of the following side effects occur:
More common
Blurred vision, change in color vision, or difficulty in seeing at night
fainting
loss of balance control
mask-like face
restlessness or need to keep moving
shuffling walk
stiffness of arms or legs
trembling and shaking of hands and fingers
Less common
Difficulty in urinating
skin rash
sunburn (severe)
Rare
Abdominal or stomach pains
aching muscles and joints
agitation, bizarre dreams, excitement, or trouble in sleeping
bleeding or bruising (unusual
clumsiness
confusion (mild)
constipation (severe)
convulsions (seizures)
dark urine
fever and chills
headaches
hot, dry skin or lack of sweating
itchy skin (severe)
muscle weakness
pain in joints
prolonged, painful, inappropriate erection of the penis
redness of hands
shivering
skin discoloration (tan or blue-gray)
sore throat and fever
sores in mouth
unusual bleeding or bruising
unusual tiredness or weakness
yellow eyes or skin
Phenothiazines may cause your urine to be dark. In most cases, this is not a sign of a serious problem. However, if your urine does become dark, discuss it with your doctor.
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
Less common
Changes in menstrual period
decreased sexual ability
increased sensitivity of eyes to light
rough or “fuzzy” tongue
secretion of milk (unusual)
swelling or pain in breasts
watering of mouth
weight gain (unusual)
After you stop using this medicine, your body may need time to adjust. The length of time this takes depends on the amount of medicine you were using and how long you used it. During this time, check with your doctor if you notice dizziness, nausea and vomiting, stomach pain, trembling of the fingers and hands, or any of the following signs of tardive dyskinesia or tardive dystonia:
Inability to move eyes
lip smacking or puckering
muscle spasms of face, neck, body, arms, or legs, causing unusual body positions or unusual expressions on face
puffing of cheeks
rapid or worm-like movements of tongue
sticking out of tongue
tic-like or twitching movements
trouble in breathing, speaking, or swallowing
uncontrolled chewing movements
uncontrolled twisting or other movements of neck, trunk, arms, or legs
Although not all of the side effects listed above have been reported for all of the phenothiazines, they have been reported for at least one of them. However, since all of the phenothiazines are very similar, any of the above side effects may occur with any of these medicines.
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Available as a lower-cost generic medication
Comes as a tablet, liquid, or injection (both short- and long-acting)
Dose can be easily adjusted based on individual needs
Long-term use can raise the risk of permanent movement problems
Not safe for use in older adults with dementia-related psychosis
Might not be a safe option if you've had a bad reaction to similar medications (e.g., chlorpromazine (Thorazine), thioridazine (Mellaril))
Your fluphenazine dose can change a lot, especially when you first start the medication. Make sure you know how much you should take and how often.
If you're using a liquid form of fluphenazine, be sure to use the measuring device provided by your pharmacy to measure out your dose. Household spoons aren't accurate and can cause you to take too much or too little of the medication.
If you're using the oral concentrate, mix the medication with 2 fl oz (60 mL) of liquid right before you take your dose. The medication can be mixed with tomato or fruit juice (except apple), milk, or non-caffeinated soda. Don't mix the medication with apple juice or caffeinated drinks (e.g., coffee, tea, cola) because they aren't compatible with fluphenazine.
Don't suddenly stop taking fluphenazine unless directed by your provider. Suddenly stopping the medication after taking high doses for a long time can lead to unpleasant effects. Your provider might want you to lower your dose slowly over time.
Fluphenazine can cause dizziness, sleepiness, and can affect your ability to focus, think, and react. Don't drive or do anything that requires you to focus until you know how this medication affects you.
Fluphenazine can lower your blood pressure when you stand from a seated or lying down position. This can cause dizziness and raise your risk of falls and injuries. Stand up slowly and brace yourself when switching positions.
Fluphenazine can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Risk factors: Age 65 and older with dementia and psychosis
People over the age of 65 who have dementia sometimes have some of the symptoms of psychosis, like hallucinations and delusions. This is called dementia-related psychosis, and it shouldn't be treated with fluphenazine. If fluphenazine is used for dementia-related psychosis, it can cause death. Let your provider know if you or your loved one has dementia before starting fluphenazine.
Risk factors: Age 65 and older | Females aged 65 and older | Taking fluphenazine for a long time | Taking high doses
Antipsychotic medications like fluphenazine can cause a movement condition called tardive dyskinesia (TD). Common symptoms of TD include uncontrollable facial movements such as blinking or sticking out your tongue. It happens more often to older adults, especially older women, but can happen to anyone. Let your provider know if this starts to happen to you or a loved one if you're a caregiver. Sometimes TD will go away if fluphenazine is stopped or the dose is lowered.
Fluphenazine can cause a rare but life-threatening condition called neuroleptic malignant syndrome (NMS). Symptoms include high fever, fast heart rate, full body stiffness, and confusion. Get medical attention right away if you notice any of these symptoms. Your healthcare provider will likely find you another medication that will work better for you.
Risk factors: History of low white blood cell counts
Fluphenazine can lower the number of white blood cells you have. White blood cells help your body to fight off infections and diseases. If you notice a fever or that you're getting sick more easily, let your provider know right away because they might have you stop taking this medication. Talk to your provider if you think you're getting sick more often.
Fluphenazine can cause prolactin hormone levels in your blood to go up. High prolactin levels can lead to a milky substance being released from the nipple, enlarged breasts, sexual dysfunction, absent or irregular menstrual periods, and weak bones. Your provider might do regular blood tests to make sure that your prolactin levels are in a healthy range.
Fluphenazine should only be used in pregnancy if the benefits outweigh the potential risks to your unborn baby. Newborn babies exposed to fluphenazine during the third trimester of pregnancy are at a higher risk for side effects and withdrawal symptoms following delivery. Let your healthcare provider know if you're pregnant or plan to become pregnant while taking fluphenazine.
Fluphenazine hydrochloride
Oral (tablets, liquid elixir, liquid concentrate): The typical starting dose ranges from 2.5 mg to 10 mg by mouth daily, split into 3 or 4 doses throughout the day (every 6-8 hours). Your provider might adjust your dose based on how you respond to the medication.
Injection: The typical starting dose ranges from 2.5 mg to 10 mg injected into the muscles daily, split into 3 or 4 doses throughout the day (every 6-8 hours). Your provider might adjust your dose based on how you respond to the medication.
Fluphenazine decanoate
Long-acting fluphenazine injection is only prescribed by providers for people who've already tried and been stable on the short-acting fluphenazine hydrochloride.
Injection: The typical starting dose ranges from 12.5 mg to 25 mg injected under the skin or into the muscles, typically once every 4 to 6 weeks, by a healthcare provider in a clinic setting. Your provider might adjust your dose based on how you respond to the medication.
Your dose might differ if you're 65 years or older.
Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking any of these medicines, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Using medicines in this class with any of the following medicines is not recommended. Your doctor may decide not to treat you with a medication in this class or change some of the other medicines you take.
Using medicines in this class with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Brain damage or suspected to have brain damage
Taking large doses of hypnotics
Coma
Severe depression
Having severe blood or liver problems
Psychotic and behavioral disorders
Tourette syndrome in adults and children
Hyperactivity in children
Schizophrenia - people ages 13 years and older
Manic or mixed episodes associated with bipolar I disorder - people ages 10 years and older
Irritability associated with autism - children ages 5 to 17 years old
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