(FDA approved in bold)

• Chorea in Huntington’s disease (HD)
  
• Dyskinesias in HD
  
• Psychosis
  
• Hemiballism
  
• Dystonia (especially tardive)
  
• Myoclonus
  
• Gilles de la Tourette syndrome (GTS) or tics
  
• Hypertension

• Depleting agent that reversibly depletes stores of monoamines (dopamine, norepinephrine, serotonin, and histamine) from nerve terminals and blocks post-synaptic dopamine receptors. Effectiveness is likely related to dopamine depletion

• Usually less than 1 week

• In neurologic conditions, continue to assess effect of the medication, determine if still needed and adjust to optimal dose

• Chorea: Consider benzodiazepines and anticonvulsants (valproate). Neuroleptics are usually effective. Reserpine is an alternative depleting agent
  
• Generalized dystonia: Anticholinergics, baclofen, or benzodiazepines may be effective. Surgical treatments (including pallidotomy, thalamotomy, deep brain stimulation, myotomy, rhizotomy, or peripheral denervation) are reserved for refractory cases
  
• GTS/tics – Neuroleptics and alpha-2 adrenergic agonists are often effective

• Chorea – combine with anticonvulsants, neuroleptics, or benzodiazepines
  
• Dystonia – combine with anticholinergics or benzodiazepines
  
• GTS/tics – Combine with neuroleptics for refractory cases

• At doses of 50 mg or greater, test patients for the CYP-450 2D6 gene to determine if they are poor, intermediate, or extensive metabolizers