Effects of zonisamide on BAEP, SSEP and P300

The effects of zonisamide on BAEP, SSEP and P300 were studied. The subjects were 12 patients (4 men and 8 women) with untreated epilepsy. Their ages ranged from 16 to 59 years, with a mean of 26.3 +/- 12.0 years. The daily dose of zonisamide was between 200 mg. to 600 mg. (2 to 6 tablets, 2.9 +/- 1.1 tablets on average). The serum concentrations of zonisamide ranged from 11.4 to 32.5 micrograms/ml, with a mean of 18.7 +/- 8.5 micrograms/ml 1 year after administration. Central conduction time and latency in BAEP and SSEP and amplitude, response time and latency in P300 were investigated. There were no significant differences in any of the tests. Zonisamide did not affect any of these evoked responses and may be less toxic to the central nervous system than other antiepileptic drugs.