Fluphenazine

This form:

Warning

There may be a slightly increased risk of serious, possibly fatal side effects (such as heart failure, fast/irregular heartbeat, pneumonia) when this medication is used by older adults with dementia. This medication is not approved for the treatment of dementia-related behavior problems. Discuss the risks and benefits of this medication, as well as other effective and possibly safer treatments for dementia-related behavior problems, with the doctor.

Precautions

Before taking fluphenazine, tell your doctor or pharmacist if you are allergic to it; or to other phenothiazines (such as chlorpromazine, perphenazine); or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of: brain damage, nervous system problems (such as CNS depression, cerebrovascular insufficiency, brain tumors, encephalitis, encephalopathy), blood problems (such as leukopenia, thrombocytopenia, agranulocytosis), liver problems, breast cancer, eye problems (such as glaucoma), heart problems (such as very high or very low blood pressure, mitral valve insufficiency), kidney problems, a certain adrenal gland tumor (pheochromocytoma), seizures, exposure to phosphorus insecticides, chronic breathing problems (such as asthma, emphysema, frequent infections), low blood calcium, enlarged prostate, drug or alcohol dependency, Reye's syndrome, dehydration.

Before having surgery or any diagnostic testing, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

This drug may make you dizzy or drowsy or blur your vision. Alcohol or marijuana (cannabis) can make you more dizzy or drowsy. Do not drive, use machinery, or do anything that needs alertness or clear vision until you can do it safely. Avoid alcoholic beverages. Talk to your doctor if you are using marijuana (cannabis).

This medication may make you more sensitive to the sun. Limit your time in the sun. Avoid tanning booths and sunlamps. Use sunscreen and wear protective clothing when outdoors. Tell your doctor right away if you get sunburned or have skin blisters/redness.

This medication may make you sweat less, making you more likely to get heat stroke. Avoid doing things that may cause you to overheat, such as hard work or exercise in hot weather, or using hot tubs. When the weather is hot, drink a lot of fluids and dress lightly. If you overheat, quickly look for a place to cool down and rest. Get medical help right away if you have a fever that does not go away, mental/mood changes, headache, or dizziness.

Avoid being exposed to very cold temperatures (such as swimming in cold water). Severe lowering of your body temperature may occur.

Children may be more sensitive to the side effects of this drug, especially the side effect of uncontrolled movements. This is especially true if the child is sick (such as has chickenpox, measles, stomach flu).

Older adults may be more sensitive to the side effects of this drug, especially to facial or muscle twitching, muscle spasms/stiffness, uncontrolled movements (tardive dyskinesia), drowsiness, dizziness, lightheadedness, confusion, and possible effects on blood pressure. Drowsiness, dizziness, lightheadedness, and confusion can increase the risk of falling.

During pregnancy, this medication should be used only when clearly needed. Liver problems or birth defects may occur in infants exposed to this type of medication in the womb. Tell the doctor right away if you notice yellowing of the eyes/skin or dark urine in your infant. Babies born to mothers who have used this drug during the last 3 months of pregnancy may rarely develop symptoms including muscle stiffness or shakiness, drowsiness, feeding/breathing difficulties, or constant crying. If you notice any of these symptoms in your newborn especially during their first month, tell the doctor right away.

Since untreated mental/mood problems (such as schizophrenia) can be a serious condition, do not stop taking this medication unless directed by your doctor. If you are planning pregnancy, become pregnant, or think you may be pregnant, immediately discuss with your doctor the benefits and risks of using this medication during pregnancy.

It is unknown if this medication passes into breast milk. However, similar drugs pass into breast milk. Consult your doctor before breastfeeding.

Side Effects

Drowsiness, lethargy, dizziness, lightheadedness, nausea, loss of appetite, sweating, dry mouth, blurred vision, headache, and constipation may occur. If any of these effects last or get worse, notify your doctor or pharmacist promptly.

Dizziness and lightheadedness can increase the risk of falling. Get up slowly when rising from a sitting or lying position.

Tell your doctor right away if any of these side effects occur: muscle spasm/stiffness, shaking (tremor), restlessness, mask-like expression of the face, drooling/trouble swallowing, or shuffling walk. Your doctor may prescribe another medication to decrease these side effects.

Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Tell your doctor right away if you have any serious side effects, including: unusual mental/mood changes (such as depression, confusion, worsening of psychosis), unusual dreams, frequent urination or difficulty urinating, vision problems, weight change, swelling of the feet/ankles, fainting, skin discoloration, butterfly-shaped facial rash, joint pain, seizures.

In rare instances, this medication may increase your level of a certain hormone (prolactin). For females, this rare increase in prolactin may result in unwanted breast milk, missing/stopped menstrual periods, or difficulty becoming pregnant. For males, it may result in decreased sexual ability, inability to produce sperm, or enlarged breasts. If you develop any of these symptoms, tell your doctor right away.

Rarely, males may have a painful or prolonged erection lasting 4 or more hours. If this occurs, stop using this drug and get medical help right away, or permanent problems could occur.

Fluphenazine may rarely cause a condition known as tardive dyskinesia. In some cases, this condition may be permanent. Tell your doctor right away if you develop any unusual/uncontrolled movements (especially of the face, mouth, tongue, arms, or legs).

This medication may rarely cause a very serious condition called neuroleptic malignant syndrome (NMS). Get medical help right away if you have any of the following symptoms: fever, muscle stiffness/pain/tenderness/weakness, severe tiredness, severe confusion, sweating, fast/irregular heartbeat, dark urine, signs of kidney problems (such as change in the amount of urine).

This drug may rarely cause serious blood problems (such as agranulocytosis, leukopenia) or liver problems. Get medical help right away if you notice any of the following rare but very serious side effects: signs of infection (such as sore throat that doesn't go away, fever), easy bruising/bleeding, severe stomach/abdominal pain, yellowing of the eyes/skin.

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US -

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

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Drug information is selected from data included with permission and copyrighted by First DataBank, Inc. This is a summary and does not contain all possible information about this product. For complete information about this product or your specific health needs, ask your healthcare professional. Always seek the advice of your healthcare professional if you have any questions about this product or your medical condition. This information is not intended as individual medical advice and does not substitute for the knowledge and judgment of your healthcare professional. This information does not contain any assurances that this product is safe, effective or appropriate for you.

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Information expires December 2025.