Xenazine

Get emergency medical help if you have signs of an allergic reaction: 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 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.

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 tetrabenazine with or without food.

Call your doctor if your symptoms do not improve, or if they get worse.

You should not stop using tetrabenazine 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.

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

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 tetrabenazine again.

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 this medicine, 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 this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.

• Amifampridine
• Amisulpride
• Bepridil
• Brofaromine
• Cisapride
• Clorgyline
• Dronedarone
• Furazolidone
• Iproniazid
• Isocarboxazid
• Lazabemide
• Linezolid
• Mesoridazine
• Moclobemide
• Nialamide
• Pargyline
• Phenelzine
• Pimozide
• Piperaquine
• Procarbazine
• Rasagiline
• Reserpine
• Saquinavir
• Selegiline
• Sparfloxacin
• Terfenadine
• Thioridazine
• Toloxatone
• Tranylcypromine
• Ziprasidone

Using this medicine 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.

• Acecainide
• Ajmaline
• Alfuzosin
• Amiodarone
• Amitriptyline
• Amoxapine
• Anagrelide
• Apomorphine
• Aripiprazole
• Arsenic Trioxide
• Artemether
• Asenapine
• Astemizole
• Azimilide
• Azithromycin
• Bedaquiline
• Bretylium
• Buserelin
• Chloroquine
• Chlorpromazine
• Ciprofloxacin
• Citalopram
• Clarithromycin
• Clomipramine
• Clozapine
• Crizotinib
• Cyclobenzaprine
• Dabrafenib
• Dasatinib
• Degarelix
• Delamanid
• Desipramine
• Deslorelin
• Disopyramide
• Dofetilide
• Dolasetron
• Domperidone
• Donepezil
• Droperidol
• Efavirenz
• Erythromycin
• Escitalopram
• Flecainide
• Fluconazole
• Fluoxetine
• Gatifloxacin
• Gemifloxacin
• Gonadorelin
• Goserelin
• Granisetron
• Halofantrine
• Haloperidol
• Histrelin
• Hydroquinidine
• Hydroxychloroquine
• Hydroxyzine
• Ibutilide
• Iloperidone
• Imipramine
• Ivabradine
• Ketoconazole
• Lapatinib
• Leuprolide
• Levofloxacin
• Lopinavir
• Lumefantrine
• Mefloquine
• Methadone
• Metronidazole
• Mifepristone
• Moxifloxacin
• Nafarelin
• Nilotinib
• Norfloxacin
• Nortriptyline
• Octreotide
• Ofloxacin
• Olanzapine
• Ondansetron
• Paliperidone
• Panobinostat
• Pasireotide
• Pazopanib
• Perflutren Lipid Microsphere
• Pimavanserin
• Pirmenol
• Pitolisant
• Posaconazole
• Prajmaline
• Procainamide
• Prochlorperazine
• Promethazine
• Propafenone
• Protriptyline
• Quetiapine
• Quinidine
• Quinine
• Ranolazine
• Risperidone
• Salmeterol
• Sematilide
• Sevoflurane
• Sodium Phosphate
• Sodium Phosphate, Dibasic
• Sodium Phosphate, Monobasic
• Solifenacin
• Sorafenib
• Sotalol
• Sulpiride
• Sunitinib
• Tacrolimus
• Tedisamil
• Telavancin
• Telithromycin
• Tetrabenazine
• Tizanidine
• Toremifene
• Trazodone
• Trifluoperazine
• Trimipramine
• Triptorelin
• Vandetanib
• Vardenafil
• Vemurafenib
• Vinflunine
• Voriconazole
• Zuclopenthixol

Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

• Paroxetine

Xenazine is part of the drug class:

• OTHER NERVOUS SYSTEM DRUGS

Tell your doctor if you are pregnant or plan to become pregnant.

The FDA categorizes medications based on safety for use during pregnancy. Five categories - A, B, C, D, and X, are used to classify the possible risks to an unborn baby when a medication is taken during pregnancy.

Xenazine falls into category C. In animal studies, pregnant animals were given this medication and had some babies born with problems. No well-controlled studies have been done in humans. Therefore, this medication may be used if the potential benefits to the mother outweigh the potential risks to the unborn child.

• Take Xenazine exactly as prescribed
• Xenazine comes in tablet form and is typically taken 1 to 3 times a day, with or without food
• During the course of your treatment with Xenazine, be alert to the emergence of any suicidal thinking or behavior, hostility, insomnia, anxiety, panic attacks, and/or depression and report all instances to your physician immediately
• Avoid use of alcohol with Xenazine
• If you stop taking Xenazine or miss a dose, involuntary movements may return or worsen
• If you miss a dose, take the missed dose as soon as you remember. If it is almost time for the next dose, skip the missed dose and take your next dose at the regular time. Do not take two doses of Xenazine at the same time

• Xenazine can increase the risk of depression, suicidal thoughts, and behavior (suicidality) in patients with Huntington's disease
• Anyone considering the use of Xenazine must balance the risks of depression and suicidality with the need for control of symptoms of chorea
• Close observation of patients for the emergence or worsening of depression, suicidality, or unusual changes in behavior should accompany therapy
• Patients, their caregivers, and families should be informed of the risk of depression and suicidality and should be instructed to report behaviors of concern promptly to the treating physician
• Particular caution should be exercised in treating patients with a history of depression or prior suicide attempts or ideation, which are increased in frequency in Huntington's disease
• Xenazine is contraindicated in patients who are actively suicidal and in patients with untreated or inadequately treated depression

Tetrabenazine reduces the amount of certain chemicals in the body that are overly active in people with Huntington's disease.

Tetrabenazine is used to treat Huntington's chorea (uncontrolled muscle movements).

Tetrabenazine may also be used for purposes not listed in this medication guide.

• Reversibly inhibits uptake of monoamines (e.g., dopamine, norepinephrine, serotonin, histamine) into synaptic vesicles and depletes monoamine stores from nerve terminals.1 2 13 17 18 19 20 21 23 24 25

• Precise mechanism of antichorea effects not established, but appears to be related to drug's ability to reversibly and selectively inhibit vesicular monoamine transporter type 2 (VMAT2) in CNS, thereby decreasing uptake of monoamines into synaptic vesicles and depleting monoamine stores from nerve terminals.1 2 7 8 13 17 18 19 20 21 23 24 25

• Preferentially depletes dopamine; dose required to deplete norepinephrine or serotonin is approximately fivefold higher than that required to deplete dopamine.2 7 17 21 23 Preferential depletion of dopamine in striatum may contribute to antichorea effects.4 13 18 22

• Exhibits weak in vitro binding affinity for dopamine type 2 (D2) receptors.1 13 21 23 Does not possess binding affinity for GABA, glutamate, glycine, histamine, or norepinephrine receptors or ion channels.7

In the U.S.

• Xenazine

Available Dosage Forms:

• Tablet

Therapeutic Class: Central Nervous System Agent

Pharmacologic Class: Monoamine Depletor

Chemical Class: Benzoquinolizine

• Tell all of your health care providers that you take this medicine. This includes your doctors, nurses, pharmacists, and dentists.
• Avoid driving and doing other tasks or actions that call for you to be alert or have clear eyesight until you see how Xenazine affects you.
• Have your blood pressure checked often. Talk with your doctor.
• Avoid alcohol or other drugs and natural products that slow your actions.
• Tell your doctor if you are pregnant or plan on getting pregnant. You will need to talk about the benefits and risks of using this medicine while you are pregnant.
• Tell your doctor if you are breast-feeding. You will need to talk about any risks to your baby.

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.

Applies to tetrabenazine: oral tablet

Along with its needed effects, tetrabenazine (the active ingredient contained in Xenazine) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking tetrabenazine:

• Body aches or pain
• chills
• cough
• difficulty in breathing
• difficulty with swallowing
• discouragement
• drowsiness
• ear congestion
• fear or nervousness
• feeling sad or empty
• fever
• headache
• inability to sit still
• irritability
• lack of appetite
• loss of balance control
• loss of interest or pleasure
• loss of voice
• mask-like face
• nasal congestion
• need to keep moving
• relaxed and calm
• restlessness
• runny nose
• shuffling walk
• sleepiness or unusual drowsiness
• sleeplessness
• slow movement or reflexes
• slurred speech
• sneezing
• sore throat
• stiffness of arms and legs
• tic-like (jerky) movements of the head, face, mouth, and neck
• tiredness
• trembling and shaking of fingers and hands
• trouble concentrating
• trouble sleeping
• trouble with balance
• unable to sleep
• unusual tiredness or weakness

• Burning while urinating
• changes in patterns and rhythms of speech
• cough producing mucus
• difficult or painful urination
• dizziness
• shortness of breath
• tightness in chest
• trouble in speaking
• trouble in walking
• wheezing

Get emergency help immediately if any of the following symptoms of overdose occur while taking tetrabenazine:

• Blurred vision
• diarrhea
• dizziness, faintness, or lightheadedness when getting up from a lying or sitting position suddenly
• fixed position of the eye
• inability to move eyes
• increased blinking or spasms of the eyelid
• mood or mental changes
• nausea and vomiting
• seeing, hearing, or feeling things that are not there
• shakiness in legs, arms, hands, or feet
• sticking out of tongue
• sweating
• trembling or shaking of hands or feet
• uncontrolled twisting movements of neck, trunk, arms, or legs
• unusual facial expressions

Some side effects of tetrabenazine 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:

• Bruising
• large, flat, blue, or purplish patches in the skin

• Decreased appetite