Nervous system side effects including dizziness (38%), ataxia (22%), somnolence (14%), incoordination (6%), insomnia (6%), tremor (4%), depression (4%), anxiety (4%), convulsion (3%), irritability (3%), speech disorder (3%), and concentration disturbance (2%) have been reported. Two cases of aseptic meningitis have been reported. Exacerbation of Parkinsonian symptoms in patients with preexisting Parkinson's