tetrabenazine

Taking tetrabenazine (Xenazine) can make you depressed and cause you to have thoughts of suicide or harming yourself, especially if you have Huntington's disease. Your provider might screen you for depression and suicidal thoughts throughout your treatment. If you or anyone around you notice that you have suicidal thoughts, feelings of depression, or unusual behavior (e.g., anxiety, panic attacks, difficulty sleeping, feeling angry or irritated, restlessness) while taking tetrabenazine (Xenazine), call your provider right away. If your depression or suicidal thoughts don't go away, you might have to stop taking tetrabenazine (Xenazine).

Huntington's disease is a condition that can cause changes in mood, ability to think clearly, chorea, muscle stiffness, and ability to function normally over time. Medications like tetrabenazine (Xenazine) can also worsen these symptoms as well. If you're taking tetrabenazine (Xenazine) and have Huntington's disease, your provider will examine you every so often to make sure this medication is safe and working properly for you. You might need to stop taking tetrabenazine (Xenazine) for a period of time to see if your symptoms are due to your Huntington's disease or the medication. If your chorea has improved, your provider might lower your dose or even have you stop taking tetrabenazine (Xenazine).

Most people respond to doses of up to 50 mg of tetrabenazine (Xenazine) per day. However, if your symptoms aren't controlled with 50 mg per day, you might need to get genetic testing done for a specific enzyme that metabolizes (breaks down) tetrabenazine (Xenazine). The presence and properties of this enzyme affects how fast your body breaks down the medication, which affects the level of tetrabenazine (Xenazine) in your body and how well the medication works. Your dose will be adjusted based on information about the properties of this enzyme from the genetic testing. If this test shows you break down tetrabenazine (Xenazine) quickly, you'll need a dose of up to 100 mg per day to treat your symptoms.

Tetrabenazine (Xenazine) can cause a rare, but life-threatening condition called neuroleptic malignant syndrome (NMS). Symptoms include high fever, sweating, stiff muscles, confusion, not being aware of your surroundings, and fast or irregular heartbeat. Your risk is higher if you take other medications that can cause NMS, such as antipsychotics (e.g., haloperidol (Haldol), risperidone (Risperdal), olanzapine (Zyprexa)). If you experience any of these symptoms while taking tetrabenazine (Xenazine), get medical attention as soon as possible. You'll likely have to stop taking tetrabenazine (Xenazine) and be switched to another medication.

Tetrabenazine (Xenazine) can make you feel restless (like you can't sit still), squirmy or fidgety, or agitated. These are signs of a complex movement problem called akathisia.

Although rare, tetrabenazine (Xenazine) can delay when your heart squeezes (contracts) and then relaxes. This condition is known as QT prolongation and can raise the risk for life-threatening abnormal heart rhythms. Your risk for QT prolongation is higher if you have a low heart rate, low potassium or magnesium blood levels, or take other medications that cause QT prolongation. Make sure to tell your provider about all the medications you're taking, and don't start any new medications or supplements while taking tetrabenazine (Xenazine) without talking to your provider or pharmacist first. People born with QT prolongation or have a history of arrhythmias should avoid taking tetrabenazine (Xenazine). If you feel your chest pounding, short of breath, chest pain, feeling faint, or lightheaded while taking tetrabenazine (Xenazine), call 911 right away, so you can be examined for this heart rhythm problem right away.