Generic name: tetrabenazine (TET ra BEN a zeen)
Brand name: Xenazine
Drug class: VMAT2 inhibitors
Xenazine (tetrabenazine) reduces the amount of certain chemicals in the body that are overly active in people with Huntington's disease.
Xenazine is used to treat Huntington's chorea (uncontrolled muscle movements).
Xenazine may also be used for purposes not listed in this medication guide.
Warnings
You should not use Xenazine if you have severe or untreated depression, suicidal thoughts, liver disease, or if you have taken reserpine in the past 20 days.
You may have depression or thoughts about suicide while taking this medicine. Stay alert to changes in your mood or symptoms. Report any new or worsening symptoms to your doctor.
Do not use Xenazine if you have used an MAO inhibitor in the past 14 days. A dangerous drug interaction could occur. MAO inhibitors include isocarboxazid, linezolid, methylene blue injection, phenelzine, rasagiline, selegiline, tranylcypromine, and others.
Stop taking Xenazine and call your doctor at once if you have any new or worsening symptoms such as: mood or behavior changes, confusion, trouble swallowing, problems with balance, uncontrolled muscle movements, extreme drowsiness, or if you feel restless, agitated, hyperactive (mentally or physically), depressed, or have thoughts about suicide or hurting yourself.
Before taking Xenazine
You should not use Xenazine if you are allergic to tetrabenazine, or if you have:
- severe or untreated depression;
- suicidal thoughts;
- liver disease; or
- if you have taken reserpine in the past 20 days.
Do not use Xenazine if you have used an MAO inhibitor in the past 14 days. A dangerous drug interaction could occur. MAO inhibitors include isocarboxazid, linezolid, methylene blue injection, phenelzine, rasagiline, selegiline, tranylcypromine, and others.
To make sure Xenazine is safe for you, tell your doctor if you have:
- depression, an emotional disorder, or mental illness;
- a history of suicidal thoughts or actions;
- past or present breast cancer;
- heart disease or heart rhythm disorder;
- a personal or family history of long QT syndrome; or
- if you recently had a heart attack.
Taking Xenazine may increase your risk of depression or thoughts about suicide. Your doctor should check your progress at regular visits. Your family or other caregivers should also be alert to changes in your mood or symptoms.
It is not known whether Xenazine will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.
It is not known whether tetrabenazine passes into breast milk or if it could harm a nursing baby. You should not breast-feed while using this medicine.
How should I take Xenazine?
Take Xenazine exactly as prescribed by your doctor. Follow all directions on your prescription label. Your doctor may occasionally change your dose to make sure you get the best results. Do not use this medicine in larger or smaller amounts or for longer than recommended.
You may take Xenazine with or without food.
Call your doctor if your symptoms do not improve, or if they get worse.
You should not stop using Xenazine suddenly or your symptoms may return. Talk to your doctor before you stop taking this medicine.
Store at room temperature away from moisture and heat.
Dosing information
Usual Adult Dose for Huntington Disease:
Initial dose:
First week: 12.5 mg orally daily
Second week: 12.5 mg orally 2 times daily
Maintenance dose:
Titrate by 12.5 mg orally weekly to tolerated dose that reduces chorea
Maximum dose:
37.5 to 50 mg daily should be administered in 3 divided doses
Maximum recommended single dose: 25 mg
What happens if I miss a dose?
Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.
If you miss your doses for more than 5 days in a row, ask your doctor before you start taking Xenazine again.
What happens if I overdose?
Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.
What to avoid
This medicine may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert.
Drinking alcohol with this medicine can cause side effects.
Xenazine side effects
Get emergency medical help if you have signs of an allergic reaction to Xenazine: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
Report any new or worsening symptoms to your doctor, such as: mood or behavior changes, anxiety, panic attacks, trouble sleeping, or if you feel impulsive, irritable, agitated, hostile, aggressive, restless, hyperactive (mentally or physically), more depressed, or have thoughts about suicide or hurting yourself.
Call your doctor at once if you have:
- tremors, shaking, restless movement, problems with balance;
- uncontrolled muscle movements in your face (chewing, lip smacking, frowning, tongue movement, blinking or eye movement);
- trouble swallowing;
- fast or pounding heartbeats;
- a light-headed feeling, like you might pass out; or
- severe nervous system reaction--very stiff (rigid) muscles, high fever, sweating, confusion, fast or uneven heartbeats.
Common Xenazine side effects may include:
- drowsiness, tiredness;
- depressed mood;
- nausea; or
- feeling anxious, agitated, or restless.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
What other drugs will affect Xenazine?
Other drugs may interact with tetrabenazine, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell each of your health care providers about all medicines you use now and any medicine you start or stop using.