FRIDAY, Aug. 15 (HealthDay News) -- Xenazine (tetrabenazine) has been approved by the U.S. Food and Drug Administration as the first drug to treat chorea, the jerky involuntary movement that occurs in people with Huntington's disease.

It's the first FDA-approved treatment of any symptom of Huntington's, an inherited disorder that affects about 30,000 people in the United States, the agency said Friday in a news release. Another 200,000 people are at risk of developing the rare neurologic disease. People who develop Huntington's typically start to have symptoms between ages 30 and 50.

Xenazine suppresses the ability of dopamine to work as a chemical communicator between certain nerve cells in the brain. In people with Huntington's, this system is overactive, causing chorea.

The drug can have serious side effects, including suicidal thoughts and depression, the agency warned. It shouldn't be used in patients who are suicidal or in those with untreated depression.

Less severe side effects could include insomnia, drowsiness, restlessness and nausea.

Xenazine is manufactured by Prestwick Pharmaceuticals of Washington, D.C.

More information

To learn more about Huntington's disease, visit the U.S. National Institute of Neurological Disorders and Stroke.