Anxiolytics, such as diazepam, alpralozam, and clonazepam, may be helpful to control agitation. We also sometimes use carbamazepine, valproate, and lithium to help control manic behavior. Impulse control problems may respond to a trial with clonidine or propranolol. Rarely, electroconvulsive therapy is sometimes required in patients with medically intractable depression. Clozapine, an atypical antipsychotic drug that does not cause tardive dyskinesia, may be a useful alternative to the typical neuroleptics, but its high cost, risk of agranulocytosis, and other potential side effects limit its use.
Neuroleptics are the most effective drugs in the treatment of chorea.
The dopamine blocking drugs, however, may cause tardive dyskinesia. Monoamine depleting drugs, such as reserpine and tetrabenazine, have the advantage that they do not cause tardive dyskinesia. Both classes of neuroleptics may cause or exacerbate depression, sedation, akathisia and parkinsonism. Recent studies have demonstrated that administration of agents which improve energy metabolism, such as coenzyme Q10 and nicotinamide, may protect animals against toxicity produced by malonate, a complex II inhibitor. Although coenzyme Q10 and nicotinamide may eventually prove to exert neuroprotective effect in humans, only symptomatic treatment is currently available for HD patients.