Tetrabenazine in the treatment of Huntington's chorea and other hyperkinetic movement disorders.

Tetrabenazine (Nitoman, Roche) is a synthetic benzoquinolizine derivative which resembles reserpine pharmacologically and depletes dopamine and other monoamines in the central nervous system. Considerable evidence has now been accumulated regarding the physiologic equilibrium which exists between dopamine and acetylcholine in the human striatum and it appears that dopamine excess or dopaminergic receptor supersensitivity are mechanisms operating in hyperkinetic disorders like Huntington's Chorea. The treatment of hyperkinetic disorders by dopamine depleting agents, like tetrabenazine or reserpine, or by dopamine blocking agents, like Haloperidol and Pimozide, has not been tried for more than a decade. We report here our own observations in 15 patients with various hyperkinetic disorders treated with tetrabenazine in doses up to 200 mgm. daily for periods up to 12 months.