Xenazine

Generic name: Tetrabenazine

Drug class: VMAT2 inhibitors

Dosage forms: Tablet

Root of administration: Oral

Dose: 12.5, 25mg

Mechanism of action: Xenazine is thought to work by changing the level of natural substances in the brain that control muscle movement. Xenazine is from the class of medications called vesicular monoamine transporter 2 (VMAT2) inhibitors. Xenazine has its effect by blocking the protein VMAT2 which lowers the amount of messenger chemicals (dopamine, serotonin, norepinephrine, and histamine) in the nerve cells, which is how it is thought to help control involuntary body movements.

Drug usage cases: Xenazine (tetrabenazine) is an FDA-approved medicine used to treat involuntary movements (chorea) caused by Huntington’s disease, which is a rare, inherited disease that causes nerve cells in the brain to breakdown and die. Xenazine helps control involuntary body movement of Huntington’s disease, but does not help the psychiatric and thinking (cognitive) symptoms, and it does not cure the disease.

Drug contra indications: You should not use Xenazine if you are allergic to it or any of the inactive ingredients 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.

Side effects: 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. Xenazine may cause serious side effects. 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.

Warnings: 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. You should not use this medicine 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.

Use during pregnancy or breastfeeding: It is not known whether this medicine will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant. It is not known whether Xenazine passes into breast milk or if it could harm a nursing baby. You should not breastfeed while using this medicine.