Snapshot A 53-year-old man presents with involuntary jerking movement of the arms. This is worsened with voluntary movement and appears to be nonrepetitive. He tries to incorporate these movements into voluntary movement. He states that this is negatively affecting his quality of life, as he has difficulty with activities of daily living. Family history is significant for Huntington's disease in the father. On physical examination, there is impaired fine motor movements and choreiform movement of the upper extremity. He is started on tetrabenazine. Introduction Huntington's disease (HD) autosomal dominant neurodegenerative disorder secondary to CAG repeat on chromosome 4 characterized by chorea, psychiatric disturbance, and cognitive decline no known cure; therefore, treatment is symptomatic changes in neurotransmitters with HD ↑ dopamine, ↓ GABA, and ↓ACh ↑ dopamine can lead to hyperkinesis (via nigro-striatal pathway) psychosis (via meso-limbic pathway) Medications treatment for chorea tetrabenazine vesicular monoamine transporter (VMAT) inhibitor impairs monoamine uptake into vesicles (e.g., dopamine, norepinephrine, and serotonin) treatment for psychiatric and behavioral symptoms psychosis/agitation antipsychotics e.g., haloperidol (typical) and risperidone (atypical) dopamine-2 receptor antagonist depression serotonin re-uptake inhibitors (SSRIs) tricyclic antidepressants (TCAs) inhibits re-uptake of norepinephrine and serotonin