Management of chorea in patients with Huntington disease

VMAT2: vesicular monoamine transporter type 2; CYP2D6: cytochrome P450 2D6; PRN: as needed.
* VMAT2 inhibitors approved for use in patients with Huntington disease are tetrabenazine and deutetrabenazine. Deutetrabenazine has a longer half-life. Availability and cost may vary by region.
¶ When switching from a VMAT2 inhibitor to antipsychotic therapy, begin antipsychotic therapy and then gradually taper VMAT2 inhibitor. Preferred second-generation antipsychotic drugs for chorea are aripiprazole, olanzapine, and risperidone.
Δ Some experts may consider a VMAT2 inhibitor in patients with comorbid depression who have refractory chorea; others consider depression a strict contraindication to VMAT2 inhibitor use in this population.