Blood homocysteine, folate and vitamin B-12 concentrations in patients with epilepsy receiving lamotrigine or sodium valproate for initial monotherapy.

To evaluate whether the administration of lamotrigine (LTG) or valproate (VPA) changes concentrations of plasma total homocysteine (tHcy), plasma and red-cell folate and plasma Vitamin B-12, we measured these indices in a total of 20 patients with epilepsy before and after a 32-week period of monotherapy of LTG or VPA. We found that the 32-week administration of a mean daily dose of 250mg LTG had no significant effect on any of the blood indices. On the other hand, the administration of a mean daily dose of 2070mg of VPA resulted in a 57% increase in plasma Vitamin B-12 concentrations over the baseline value and a 27% decline in plasma tHcy concentrations, although the mechanisms of such changes are unknown. Our data indicate that hyperhomocysteinemia may not be a serious clinical problem among patients with epilepsy, who receive either LTG or VPA.