- Selective inhibitor of vesicular monoamine transporter-2 (VMAT2)
- Decreases Dopamine release at nerve endings (Synapse)
- Reduces symptoms by 50% with 6 weeks of treatment (Number Needed to Treat: 4)
- Valbenazine (Ingrezza)
- Start 40 mg once daily and may increase to 80 mg after 1 week
- Target: 40-80 mg once daily
- Very expensive ($5000 per month)
- Strong CYP3A4 Inhibitors (e.g. Clarithromycin, Itraconazole)
- Increases Valbenazine levels
- Limit maximum Valbenazine dose to 40 mg daily
- Strong CYP3A4 inducers (e.g. Carbamazepine, Phenytoin)
- Decreases levels
- Avoid while taking Valbenazine
- Strong CYP2D6 Inhibitors (e.g. Fluoxetine, Paroxetine)
- May increase Valbenazine levels and may require reduced Valbenazine doses
-
Liver and renal metabolism
- Avoid Valbenazine use in GFR <30 ml/min
- Consider reduced Valbenazine dose in liver Impairment
- Pregnancy safety is unknown
- (2017) Presc Lett 24(6): 36
- LoVecchio (2018) Crit Dec Emerg Med 32(6): 32
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