Dopamine blockers
When pharmacological treatment is necessary, the most standard type of drug to use is an antidopaminergic drug. Blocking dopamine is effective in about ninety percent of patients. Perphenazine, pimozide, haloperidol, and chlorpromazine are standard choices for treatment. Scientists are still unsure as to why this form of treatment works, as dopamine has not been directly linked to hemiballismus. Anticonvulsants
An anticonvulsant called topiramate has helped patients in three cases and may be a viable treatment for the future. ITB therapy
Intrathecal baclofen (ITB) therapy is used to treat a variety of movement disorders such as cerebral palsy and multiple sclerosis. It can also be a possibility to help treat hemiballismus. In one case, before ITB the patient had an average of 10–12 ballism episodes of the right lower limb per hour. During episodes, the right hip would flex up to about 90 degrees, with a fully extended knee. After an ITB pump was implanted and the correct dosage was found, the frequency of ballistic right leg movements decreased to about three per day, and the right hip flexed to only 30 degrees. The patient was also able to better isolate individual distal joint movements in the right lower limb. The patient currently receives 202.4 microg/day of ITB and continues to benefit almost 6 years after the ITB pump was implanted. Botulinum injections
New uses for botulinum toxin have included treatment of hemiballismus. However, this is still in the early stages of testing. This treatment deals with the muscular manifestations of hemiballismus as opposed to the neurological causes.
Research is being done in these areas in order to give scientists and clinicians a better model for this disease that will ultimately lead to better diagnosis and treatment of this disorder. Research is also being done on why certain treatments seem to help hemiballistic patients when they should seemingly do more harm. An example of this is why lesioning the globus pallidus seems to reduce hemiballistic movements. The mechanism behind the effect of dopamine on patients symptoms remains unknown. History
The work of J.R. Whittier, F.A. Mettler, and M.B. Carpenter in the mid-1900s helped scientists and clinicians form a more complete picture of hemiballismus. In their experiments, several lesions were made in the basal ganglia structures in monkeys and then they monitored the results. They noticed that the majority of the time, the monkeys did not have any unusual movements. However, when at least twenty percent of the subthalamic nucleus was damaged, abnormal movements were seen in the limbs opposite to the side of the brain that was damaged. This observation caused scientists to believe that hemiballismus outside the subthalamic nucleus did not occur. It was not until much later that this classical model began to expand to include other areas of the basal ganglia and even some cortical structures. They also noticed that unlike human patients, the unusual movements in the monkeys were mainly in the lower extremities.