The Impact of Topiramate on Brainstem Evoked Potentials

Aim: The brainstem auditory evoked potentials (BAEP) have been used to determine the neurotoxicity of antiepileptic drugs. In the literature, there is no data about the effect of topiramate (TPM) on brainstem auditory pathways. We evaluated BAEP of patients with epilepsy before and after three months of TPM administration to clarify this subject. Material, methods: Our group consisted of TPM, carbamazepin (CBZ) and control groups. We compared the BAEPs of CBZ group with control, and TPM groups. We compared BAEPs of TPM group before and after TPM administration. Results: The ages of the patients and control groups in three groups were similar (p=0,29 and p=0,92). While the seizure frequency was 10,38 +/- 8,63 per month before TPM treatment and after 3,30 +/- 95 months treatment (min1, 5month, max 6months) it decreased to 4,38 +/- 6,86 per month (p=0,001). There was no statistical difference between the BAEPs of TPM group before and after therapy (for I. wave p=0,86; for III. wave p=0,72; for V. wave p=0,19; I-III interpeak latancy(ipl) p=0,97; for III-V ipl p=0,27; for I-V ipl p=0,38). There was no significant difference between CBZ and TPM groups. When comparing CBZ group with control group I-III ipl and TPM group with the control group I-Vipl was found to be longer (p=0,03; p=0,0003. Discussion: Brainstem auditory transmission was longer among patients with epilepsy; compared to control groups but in addition of TPM to the treatment caused no change in that TPM is shown to be effective on seizure frequency and have no effect on brainstem auditory pathways.