is a drug for the symptomatical treatment of hyperkinetic movement disorder
and is marketed under the trade names Nitoman
in Canada and Xenazine
in New Zealand and some parts of Europe, and is also available in the USA as an orphan drug
. On August 15
the U.S. Food and Drug Administration (FDA) approved the use of tetrabenazine to treat chorea associated with Huntington disease (HD), the first in the US. The compound has been known since the 1950s. Tetrabenazine works mainly as a VMAT-inhibitor
and as such promotes the early metabolic
degradation of the neurotransmitter dopamine
Tetrabenazine is used as a treatment, but not a cure
for hyperkinetic disorders such as:
Because tetrabenazine is closely related to the antipsychotics, many of its side effects are similar. Some of these include:
- Akathisia (aka "restless pacing" - an inability to keep still, with intense anxiety when forced to do so)
- Depression - the most common side effect, reported in roughly 15% of those who take the medication
Unlike many of the antipychotics, tetrabenazine is not known to cause Tardive dyskinesia, and in fact can be an effective treatment for the antipsychotic-induced movement disorder.
- Because of the relatively high incidence of depression, it has been recommended that people with a history of depression avoid taking tetrabenazine.
- The concomitant intake of MAO inhibitors is contraindicated.