Tetrabenazine is a reversible inhibitor of the vesicular monoamine transporter type 2 (VMAT2). It depletes the storage of neurotransmitters such as dopamine, serotonin, and norepinephrine in the presynaptic neuron. By reducing the release of these neurotransmitters, tetrabenazine helps control hyperkinetic movements associated with disorders like Huntington's disease