Side Effects

Before You Start Xenazine

Before you start taking Xenazine, you should tell your doctor about all of the prescription medications as well as non-prescription medicines, vitamins, herbal products or other supplements you are taking. Xenazine may interact with some of these medications. Make sure you tell your doctor before you start or stop any new medication, or if you change the dose of any medication or supplements you are taking. Always read the Medication Guide before starting your treatment with Xenazine. If you have any questions regarding Xenazine, be sure to talk with your doctor.

Xenazine is Not Suitable for Everyone

Some people should not take Xenazine. Xenazine may increase the chance of depression, suicidal thoughts, or suicidal actions in some patients.

Do not take Xenazine if:

You are sad (depressed) much of the time. You may become more depressed taking Xenazine.
You take medicine for depression that has not helped enough.
You think or talk about harming yourself or killing yourself (suicide.) You may be more likely to think about ending your life while taking Xenazine.
You have liver problems.
You take a monoamine oxidase inhibitor (MAOI), reserpine, or a medicine that contains reserpine. If your doctor plans to switch you from taking reserpine to Xenazine, you must wait at least 20 days after your last dose of reserpine before you start taking Xenazine. Ask your doctor or pharmacist if you are not sure.

When taking Xenazine, pay close attention to any changes in how you feel. Let your doctor know if you have sudden changes in your mood, behaviors, or thoughts. These changes may occur when you start Xenazine and when your doctor changes your dose.

Possible Xenazine Side Effects

The most common side effects of Xenazine include:

Depression, suicidal thoughts, or actions.
Neuroleptic Malignant Syndrome (NMS). Call your doctor right away and go to the nearest emergency room if you develop these signs and symptoms that do not have another obvious cause:
- high fever
- stiff muscles
- problems thinking
- very fast or uneven heartbeat
- increased sweating
Parkinsonism. Symptoms of Parkinsonism include: slight shaking, body stiffness, trouble moving or keeping your balance.
Restlessness. You may get a condition where you feel a strong urge to move. This is called akathisia.
Trouble swallowing. XENAZINE may increase the chance that you will have trouble swallowing. Increased coughing may be the first sign that you are having trouble swallowing. Trouble swallowing increases your risk of pneumonia.
Irregular heartbeat. XENAZINE increases your chance of having certain changes in the electrical activity in your heart which can be seen on an electrocardiogram (EKG). These changes can lead to a dangerous abnormal heartbeat. Taking XENAZINE with certain medicines may increase this chance.
Dizziness due to blood pressure changes when you change position (orthostatic hypotension). Change positions slowly from lying down to sitting up and from sitting up to standing when taking XENAZINE. Tell your doctor right away if you get dizzy or faint while taking XENAZINE. Your doctor may need to watch your blood pressure closely.
Tardive dyskinesia (TD). TD is a condition where there is repeated facial grimacing that cannot be controlled, sticking out of the tongue, smacking of the lips, puckering and pursing of the lips, and rapid eye blinking. XENAZINE works like other drugs that can cause TD. If you get TD with XENAZINE, it is possible that the TD will not go away.
Common side effects with XENAZINE include:
- sleepiness (sedation)
- trouble sleeping
- depression
- tiredness (fatigue)
- anxiety
- restlessness
- agitation
- nausea

You should not drive a car or operate dangerous machinery until you know how Xenazine affects you. Drinking alcohol and taking other drugs that may also cause sleepiness while you are taking Xenazine may increase any sleepiness caused by Xenazine.

Tell your doctor if you have any side effects. Do not stop taking Xenazine without talking to your doctor first.

You are encouraged to report negative side effects of Xenazine to the Xenazine Information Center (XIC) at 1-888-882-6013 or to the FDA. Visit www.fda.gov/medwatch or call 1-800-FDA-1088.

XENAZINE® (tetrabenazine) Tablets

Indications and Usage:

Xenazine is a medicine that is used to treat the involuntary movements (chorea) of Huntington’s disease. Xenazine does not cure the cause of the involuntary movements, and it does not treat other symptoms of Huntington’s disease, such as problems with thinking or emotions.

It is not known whether Xenazine is safe and effective in children.

Important Safety Information:

Xenazine can increase the chance of depression, suicidal thoughts or suicidal actions in some patients.
You should not start taking Xenazine if you are depressed (have untreated depression or depression that is not well controlled by medicine) or have suicidal thoughts.
Pay close attention to any changes, especially sudden changes, in mood, behaviors, thoughts or feelings. This is especially important when Xenazine is started and when the dose is changed.

Do not take Xenazine if you have liver problems or are taking monoamine oxidase inhibitors or reserpine. At least 20 days should pass after stopping reserpine before starting Xenazine. Tell your doctor if you are pregnant, breast-feeding or have breast cancer.

The need for therapy should be evaluated on an ongoing basis with your doctor. The dose of Xenazine should be adjusted slowly over several weeks for a dose that is appropriate for you. If your doctor thinks you need to take more than 50 mg of Xenazine each day, you will need to have a blood test to see if Xenazine is safe for you.

Neuroleptic malignant syndrome (NMS), restlessness, agitation, parkinsonism (slight shaking, body stiffness, trouble moving or keeping your balance), trouble swallowing, dizziness, and irregular heartbeat have also been reported with use of Xenazine. Do not use Xenazine with drugs known to cause irregular heart beat. Side effects associated with Xenazine, such as irregular heartbeat, NMS, and parkinsonism, may be increased if used together with drugs called dopamine antagonists. Uncontrolled movements called tardive dyskinesia (TD) may develop in patients treated with Xenazine. It is possible that the TD will not go away.

Xenazine may cause sleepiness or drowsiness, and may affect the ability to drive or use dangerous machinery. Some side effects, such as depression, tiredness, trouble sleeping, sleepiness/drowsiness, parkinsonism, and restlessness, may be dose-dependent. If the side effects don’t stop or lessen, your doctor should consider lowering the dose or stopping your Xenazine. The most commonly reported side effects in studies with Xenazine were sleepiness/drowsiness, tiredness, trouble sleeping, depression, restlessness, anxiety, and nausea.

For more information, please see the Xenazine Medication Guide and Full Prescribing Information, including Boxed Warning.

®Xenazine is a registered trademark of Biovail Laboratories International (Barbados) S.R.L.

XZN118

The product information provided in this site is intended only for residents of the U.S. The health information contained herein is provided for educational purposes only and is not intended to replace discussions with a healthcare provider.