What treatment strategies do you employ in patients with Huntington's disease who have parkinsonian features?

Many HD patients actually have clinically detectable parkinsonism, but it is often masked by other more disabling problems including chorea and psychiatric symptoms.

Thus, the use of traditional antiparkinsonian therapies can be hampered by substantial side effects.

If a patient is not on any medications, carbidopa/levodopa can be used if the parkinsonian component is disabling.

For patients on antipsychotics or VMAT-2 inhibitors, first try lowering the dose, keeping in mind that it may take a couple of weeks or more to see a positive response. If parkinsonian findings continue to be disabling, clozapine can be started. This antipsychotic can sometimes have an antiparkinsonian effect, though routine monitoring of the ANC (Absolute Neutroph...