FluPHENAZine

This information from UpToDate^® Lexidrug^™ explains what you need to know about this medication, including what it’s used for, how to take it, its side effects, and when to call your healthcare provider.

What is this drug used for?

• It is used to lower the number of tics from chronic tic disorder.
• If your child has been given this drug for some other reason, talk with the doctor about the benefits and risks. Talk with the doctor if you have questions or concerns about giving this drug to your child.

What do I need to tell the doctor BEFORE my child takes this drug?

• If your child is allergic to this drug; any part of this drug; or any other drugs, foods, or substances. Tell the doctor about the allergy and what signs your child had.
• If your child has any of these health problems: Brain injury or disease, liver disease, or blood cell problems.
• If your child has a health problem or takes a drug that makes your child very sleepy.
• If your child has recently drunk a lot of alcohol or taken a drug that may slow your child’s actions like phenobarbital or some pain drugs like oxycodone.

This is not a list of all drugs or health problems that interact with this drug.

Tell the doctor and pharmacist about all of your child’s drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe to give this drug with all of your child’s other drugs and health problems. Do not start, stop, or change the dose of any drug your child takes without checking with the doctor.

What are some things I need to know or do while my child takes this drug?

• Tell all of your child’s health care providers that your child is taking this drug. This includes your child’s doctors, nurses, pharmacists, and dentists.
• Have your child avoid tasks or actions that call for alertness until you see how this drug affects your child. These are things like riding a bike, playing sports, or using items such as scissors, lawnmowers, electric scooters, toy cars, or motorized vehicles.
• Alcohol may interact with this drug. Be sure your child does not drink alcohol.
• Talk with your child’s doctor before your child uses marijuana, other forms of cannabis, or prescription or OTC drugs that may slow your child’s actions.
• Dizziness, sleepiness, and feeling less stable may happen with this drug. These may lead to falling, which can cause broken bones or other health problems.
• This drug may make your child sunburn more easily. Use care if your child will be in the sun. Tell your child’s doctor if your child sunburns easily while taking this drug.
• Have your child be careful in hot weather or while your child is being active. Have your child drink lots of fluids to stop fluid loss.
• If your child will be near phosphorous insecticides, talk with your child’s doctor.
• Low white blood cell counts have happened with drugs like this one. This may lead to a higher chance of infection. Rarely, infections have been deadly. Tell the doctor if your child has ever had a low white blood cell count. Call the doctor right away if your child has signs of infection like fever, chills, or sore throat.
• Do not stop giving this drug to your child all of a sudden without calling the doctor. Your child may have a greater risk of side effects. If your child needs to stop this drug, you will want to slowly stop it as told by the doctor.
• Have blood work checked as you have been told by the doctor. Talk with the doctor.
• This drug may cause the results of some pregnancy tests to be wrong. Talk with the doctor.

If your child is pregnant or breast-feeding a baby:

• Talk with the doctor if your child is pregnant, becomes pregnant, or is breast-feeding a baby. You will need to talk about the benefits and risks to your child and the baby.
• Taking this drug in the third trimester of pregnancy may lead to side effects or withdrawal in the newborn.

What are some side effects that I need to call my child’s doctor about right away?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your child’s doctor or get medical help right away if your child has any of the following signs or symptoms that may be related to a very bad side effect:

• Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
• Signs of liver problems like dark urine, tiredness, decreased appetite, upset stomach or stomach pain, light-colored stools, throwing up, or yellow skin or eyes.
• Signs of high or low blood pressure like very bad headache or dizziness, passing out, or change in eyesight.
• Chest pain or pressure or a fast heartbeat.
• Shortness of breath.
• Trouble swallowing or speaking.
• Twitching.
• Change in balance.
• Drooling.
• Seizures.
• Swelling in the arms or legs.
• Change in eyesight.
• Not able to control eye movements.
• Any unexplained bruising or bleeding.
• Not able to pass urine or change in how much urine is passed.
• More interest in sex.
• Severe constipation or stomach pain. These may be signs of a severe bowel problem.
• Enlarged breasts, nipple discharge, not able to get or keep an erection, or menstrual changes.
• A very bad and sometimes deadly health problem called neuroleptic malignant syndrome (NMS) may happen. Call your child’s doctor right away if your child has any fever, muscle cramps or stiffness, dizziness, very bad headache, confusion, change in thinking, fast heartbeat, heartbeat that does not feel normal, or is sweating a lot.
• Some people may get a severe muscle problem called tardive dyskinesia. This problem may lessen or go away after stopping this drug, but it may not go away. The risk is greater with diabetes and in older adults, especially older females. The risk is greater with longer use or higher doses, but it may also occur after short-term use with low doses. Call your child’s doctor right away if your child has trouble controlling body movements or problems with the tongue, face, mouth, or jaw like tongue sticking out, puffing cheeks, mouth puckering, or chewing.

What are some other side effects of this drug?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your child’s doctor or get medical help if any of these side effects or any other side effects bother your child or do not go away:

• Feeling nervous and excitable.
• Restlessness.
• Strange or odd dreams.
• Constipation.
• Dry mouth.
• Feeling sleepy.
• Feeling tired or weak.
• Headache.
• Upset stomach.
• Decreased appetite.
• Sweating a lot.
• Weight gain or loss.

These are not all of the side effects that may occur. If you have questions about side effects, call your child’s doctor. Call your child’s doctor for medical advice about side effects.

You may report side effects to your national health agency.

How is this drug best given?

Give this drug as ordered by your child’s doctor. Read all information given to you. Follow all instructions closely.

All products:

• Have your child drink lots of noncaffeine liquids unless told to drink less liquid by your child’s doctor.
• Keep giving this drug to your child as you have been told by your child’s doctor or other health care provider, even if your child feels well.

All liquid products:

• Measure liquid doses carefully. Use the measuring device that comes with this drug. If there is none, ask the pharmacist for a device to measure this drug.

Liquid (concentrate):

• Mix this drug with at least 2 ounces (60 mL) of milk, orange soda, or some juices. Do not mix with caffeine drinks, tea, or apple juice. Take right away after mixing.

What do I do if my child misses a dose?

• Give a missed dose as soon as you think about it.
• If it is close to the time for your child’s next dose, skip the missed dose and go back to your child’s normal time.
• Do not give 2 doses at the same time or extra doses.

How do I store and/or throw out this drug?

• Store at room temperature protected from light. Store in a dry place. Do not store in a bathroom.
• Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
• Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.

General drug facts

• If your child’s symptoms or health problems do not get better or if they become worse, call your child’s doctor.
• Do not share your child’s drug with others and do not give anyone else’s drug to your child.
• Some drugs may have another patient information leaflet. If you have any questions about this drug, please talk with your child’s doctor, nurse, pharmacist, or other health care provider.
• If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

Consumer Information Use and Disclaimer

This generalized information is a limited summary of diagnosis, treatment, and/or medication information. It is not meant to be comprehensive and should be used as a tool to help the user understand and/or assess potential diagnostic and treatment options. It does NOT include all information about conditions, treatments, medications, side effects, or risks that may apply to a specific patient. It is not intended to be medical advice or a substitute for the medical advice, diagnosis, or treatment of a health care provider based on the health care provider’s examination and assessment of a patient’s specific and unique circumstances. Patients must speak with a health care provider for complete information about their health, medical questions, and treatment options, including any risks or benefits regarding use of medications. This information does not endorse any treatments or medications as safe, effective, or approved for treating a specific patient. UpToDate, Inc. and its affiliates disclaim any warranty or liability relating to this information or the use thereof. The use of this information is governed by the Terms of Use, available at https://www.wolterskluwer.com/en/know/clinical-effectiveness-terms.

Last Reviewed Date

2026-03-02

Copyright

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