Psychotic Symptoms in Huntington's are disorders of thought in which the person loses contact with reality. Symptoms include delusions, which are irrational and false beliefs about reality, and less often include hallucinations, which is seeing or hearing things that are not there. It is reported that delusions can occur in up to 11% of patients and hallucinations less frequently in 2% [Paulsen JS 2001]. Both of these symptoms occur more frequently as the disease progresses and cause great distress for the person and for families. These symptoms are the most common cause of institutionalization [Wheelock VL 2003]. Though schizophrenia can co-occur with HD, the psychosis of HD has differing features, as does the psychosis of Parkinson's disease. Antipsychotic drug treatment is more successful in treating the psychosis of schizophrenia than in Parkinson's disease, and this may be true for HD as well.

Psychosis Treatments: Antipsychotic medications are often required for these severe symptoms. There are several general points to remember about these drugs. Dosage is important. It must be adjusted to each individual for best balance of benefit and side effect. And it's important to remember that best dosage may change and often decreases if needed long term. All of these drugs can cause sedation which is improved by decreasing dose. The older first generation drugs cause more "Parkinsonism" side effects that can worsen motor function in HD more so than the newer drugs. See Antipsychotic Fact Page for more information about these drugs.

Concurrent use of SSRI antidepressant medications or clomipramine can be helpful when the delusion has obsessive features. Mood stabilizer medications can also be helpful and can often result in lower doses of antipsychotic medications. And finally, if one antipsychotic drug is not successful or gives too many side effects, another should be tried.


Paulsen JS, Ready RE, Hamilton JM, Mega MS, Cummings JL. Neuropsychiatric aspects of Huntington's disease. J Neurol Neurosurg Psychiatry. 2001 Sep;71(3):310-4. PubMed abstract

Wheelock VL, Tempkin T, Marder K, Nance M, Myers RH, Zhao H, Kayson E, Orme C, Shoulson I; Huntington Study Group. Predictors of nursing home placement in Huntington disease. Neurology. 2003 Mar 25;60(6):998-1001. PubMed abstract