Tetrabenazine - Tardive Dyskinesia Treatment
Tardive dyskinesia (TD) is classified as a movement disorder and is similar to many other conditions including Tourette's syndrome and Parkinson's disease. Although tardive dyskinesia primarily results from the side effects of drugs used to treat schizophrenia and certain digestive disorders (which are classified as dopamine antagonists and are designed to block signals from the brain to targeted cells), treating the condition is not as simple as removing the medication.
Not only does some evidence suggest that tardive dyskinesia can be triggered by sudden withdrawal from such drugs, but symptoms may appear up to several months or years after a patient has discontinued medication. Nonetheless, the most effective treatment for most tardive dyskinesia patients has been prevention – either by taking a patient off of a medication at the first signs of symptoms, limiting patient exposure to less than three consecutive months, or avoiding the use of such drugs altogether.
Managing Tardive Dyskinesia
Currently, there is no cure for tardive dyskinesia. Several treatments for the management of the disorder have been used, including a tranquilizer called chlordiazepoxide hydrochloride, known better by its trade name, Librium. Unfortunately, this drug has proved to be habit-forming, and while a few tardive dyskinesia patients have received some benefit from the drug, its effectiveness has not been great enough for the justification of its employment as a standard treatment.
Tetrabenazine as an “Orphan Drug”
In the United States, tetrabenazine has the legal status of an “orphan drug,” meaning that it is developed for the treatment of a specific, rare condition. Under U.S. law, this is defined as a condition that effects fewer than 200,000 people. Because such research is not-profitable, the federal government offers special financial incentives to these corporations to encourage the development of such medications.
tetrabenazine is used to treat one symptom of Huntington's disease, which is called chorea, a condition that is characterized by irregular, involuntary muscular contractions that apparently go from muscle to muscle. Although the drug is described as “dopamine-depleting,” what it actually does is facilitate the metabolism of dopamine, essentially helping this neurotransmitter to work more effectively. The drug is also used in the treatment of hyperkinetic (restless, compulsive movements) symptoms of Tourette's syndrome.
Risks of Tetrabenazine
While tetrabenazine has been effective in relieving the symptoms of tardive dyskinesia, it is not without its own side effects. These may include akathisia, a compulsive need to pace back and forth accompanied by inner feelings of anxiety and paranoia, dizziness, sleep difficulties or drowsiness and fatigue, and parkinsonism (tremors and muscular weakness associated with Parkinson's Disease). Approximately 15 percent of patients treated with tetrabenazine also report depression.