A preliminary study of the efficacy of ondansetron in the treatment of ataxia, poor balance and incoordination from brain injury

BACKGROUND: Ataxia is caused by a variety of conditions leading to imbalance, incoordination and other disabilities. Current treatment is largely symptomatic. Ondansetron (a 5-HT3 antagonist) has been established as an anti-emetic in cancer patients, but has recently been shown to improve vertigo and cerebellar tremor in some patients. HYPOTHESIS: Ondansetron can improve symptoms of ataxia, imbalance and incoordination in four brain-injured patients. DESIGN: Placebo-controlled, double blind, crossover, 'n of 1' study, A-B-A design. SUBJECTS: Four patients with ataxia from traumatic brain injury. METHODS: Four patients underwent five separate tests of ataxia under three different conditions in a double blind fashion. RESULTS: For all subjects, there was little difference in scores in the five areas tested, with some improvement in tests of lower limb ataxia (10.4% for 4 mg and 10.7% for 8 mg ondansetron vs baseline). CONCLUSION: Ondansetron use showed a trend towards improvement in tests of lower extremity ataxia but did not consistently improve scores in four patients.