Dalfampridine and Gait in Spinocerebellar Ataxias

Twenty spinocerebellar ataxia patients will be randomized to receive either Dalfampridine or
placebo over a total period of 10 weeks. After entering the study, patients will return
every 2 weeks for evaluation. After five weeks, intervention will be stopped and patient
will enter a 2-week wash out period where they do not take any drug. Then, patients will be
given the opposite treatment (Dalfampridine or placebo) and this "crossover" study will be
performed for another 4 weeks. Investigators expect there will be improvement in walking
speed and steadiness after taking Dalfampridine, thereby improving activities of daily
living and enhancing social and occupational functions.

Inclusion Criteria:

- Individuals at age 18 years or older.

- Individuals who can provide the informed consent

- Genetic confirmed definite spinocerebellar ataxias (SCA)

- Able to complete two trials of the timed 25-foot walk at screening

Exclusion Criteria:

- Patients who has severe ataxia and unable to ambulate.

- Any orthopedic condition that would affect motor performance.

- Patients with secondary ataxia from general medical disorders

- Individuals who have major psychiatric disorders that prevents compliance

- History of epilepsy

- Patients with active drug or alcohol use or dependence that would interfere with
adherence to study requirements

- Inability or unwillingness of subject or legal guardian/representative to give
written informed consent.