Description

Tetrabenazine is a drug formerly used as an antipsychotic but now used primarily in the symptomatic treatment of various hyperkinetic disorders, It is a vesicular monoamine transporter-2 (VMAT-2) inhibitor that used as symptomatic treatment of chorea associated with Huntington's disease.

With medicine: Strong CYP2D6 Inhibitors: A reduction in Tetrabenazine dose may be necessary when adding a strong CYP2D6 inhibitor (e.g., fluoxetine, paroxetine, quinidine) in patients maintained on a stable dose of Tetrabenazine. Reserpine: Reserpine binds irreversibly to VMAT2, and the duration of its effect is several days. At least 20 days should elapse after stopping reserpine before starting Tetrabenazine, Tetrabenazine and Reserpine should not be used concomitantly. With food & others: No interaction with food, can be taken with or without food.

Tetrabenazine is contraindicated in: Actively suicidal, or who have depression which is untreated or undertreated Hepatic impairment. Concurrent use of monoamine oxidase inhibitors (MAOIs) or reserpine. Concurrent use of deutetrabenazine or valbenazine.

Common: Most common adverse reactions (>10% and at least 5% greater than placebo) were-Sedation/somnolence, fatigue, insomnia, depression, akathisia, anxiety/anxiety aggravated & nausea. Rare: Suicidal thoughts, neuroleptic malignant syndrome, a reaction characterized by fever, muscle rigidity and confusion & pneumonia.

There are no adequate data on the developmental risk associated with the use of Tetrabenazine in pregnant women. There are no data on the presence of tetrabenazine or its metabolites in human milk.

The benefit and potential for adverse effects such as worsening mood, cognition, rigidity, and functional capacity should be periodically re-evaluated. The maximum daily dose should not exceed 50 mg/day and the maximum single dose should not exceed 25 mg if administered in conjunction with a strong CYP2D6 inhibitor (e,g., fluoxetine, paroxetine). In case of Neuroleptic Malignant Syndrome, the treatment should be discontinued. The dose should be reduced or discontinued if patient experience restlessness, agitation, akathisia and parkinsonism, The treatment may impair patient's ability to drive or operate complex machinery, Tetrabenzine is not recommended in combination with other drugs that prolong QTc.

Signs and symptoms of overdosage of Tetrabenazine may include drowsiness, sweating and hypothermia.