Tetrabenazine

It is a synthetic benzoquinolizine currently. It is a specific, high affinity, inhibitor of monoamine uptake into a granular vesicles of presynaptic neurons in the central nervous system.

Indications

Hyperkinetic movement disorders. Gilles de la Tourette's syndrome, dystonia, and segmental myoclonus.

Dosage

25 mg daily. Max daily dose: 200 mg. Maintenance dose: 50-200 mg per day.

Contra-Indications

Pregnancy, lactation. Hypersensitivity. Parkinsonism. Hypotension.

Special Precautions

Should not be administered with monoamine oxidase inhibitor. Levodopa induced dyskinetic/choreiform movements should be treated by reducing the dose of levodopa, and not by giving tetrabenazine, since the latter exacerbates Parkinsonism symptoms. It may cause drowsiness.

Side Effects

Neuroleptic malignant syndrome, Depression, Parkinsonism. Drowsiness, fatigue, nervousness and anxiety, insomnia, agitation, confusion, salivary drooling or orthostatic hypotension, nausea, dizziness.

Drug Interactions

Concomittant administration with neuroleptic agents results in severe dopamine deficiency.