Which Drug is Best for Chorea?

Medication guideline for involuntary movements associated with Huntingtons Disease released

(RxWiki News) Sorting through different medications to see which one works best for you can be a daunting task for both the patient and sometimes his or her physician. When it comes to drugs to treat chorea from Huntington's disease, the process may be getting easier.

Researchers at the University of Maryland Department of Neurology have put together a guideline that can help patients and doctors understand which medicines might work best for most people with the disease.

The American Academy of Neurology (AAN) released the new guideline assessing pharmaceutical treatment options for Huntington's disease (HD) chorea, the uncontrollable, jerking movements that are the hallmark symptoms of the disease.

The study concluded that the drugs tetrabenazine (TBZ), riluzole and amantadine can be helpful, and nabilone may also be considered.

"Talk to your doctor about your medication's risks."

Melissa J. Armstrong, MD, MSc and Janis M. Miyasaki, MD, MEd, FAAN, authors of the study advising the guideline, searched Medline and Embase for materials relevant to HD.

The search resulted in the review of 33 articles. Included articles contained either a subject with genetically confirmed HD or HD features with a family history of the disorder, a comparison group, the use of an available drug, measurement of chorea change, and at least 20 patients.

Content of the studies and ratings given by the Unified Huntington’s Disease Rating Scale (UHDRS) were considered when evaluating pharmaceuticals. The UHDRS measures the progression of HD based on motor, behavioral, cognitive and functional assessments.

HD is the most common genetic cause of uncontrollable writhing movements called chorea. Chorea develops early on in HD and progresses until it plateaus in late stages of the disorder.

Of the drugs recommended in the guideline - TBZ, riluzole, amantadine and nabilone - only TBZ is FDA-approved for treating HD chorea.

It’s important to note that HD studies usually consist of patients who are ambulatory, have good functional capacity and are free from disabling depression or cognitive decline, so as to not have these conditions affect the study results. A patient with additional conditions or atypical symptoms should take this into consideration before engaging in a treatment program.

Patients should discuss with their doctor whether their chorea requires treatment, as some studies show treatment improves quality of life and decreases disability while others show a functional and quality of life decline. When making this decision, consider any instances of mood disturbances, cognitive decline, pharmaceutical risk or additional drugs that may counteract chorea treatment.

Cost and availability are also important factors. TBZ, riluzole and nabilone can be very expensive. Also, nabilone is a class 2 substance considered to have high abuse potential.

Dr. Armstrong received support as an Edmond J. Safra Fellow at Toronto Western Hospital while working on this project, serves as a member of the AAN Guideline Development Subcommittee and as a Level of Evidence reviewer for Neurology magazine. She also receives research funding from Abbott as a study sub-investigator. Dr. Miyasaki received grants from Medivation, National Institutes of Health, and the Michael J. Fox Foundation. She also receives consultancy fees from Novartis and Mertz for Data and Safety Monitoring, speaking fees from Teva and is a member of the Board of Directors of the American Academy of Neurology.

Reviewed by: 
Review Date: 
July 18, 2012