Worsening in seizure frequency and severity in relation to folic acid administration

We report a case of increase in seizure frequency and severity in a 26-year-old woman receiving folic acid at a dosage of 0.8 mg/day. She had symptomatic partial epilepsy with simple and complex seizures treated with carbamazepine. She was planning pregnancy and we prescribed folic acid for prevention of neural-tube defects. In the next few days she had a generalized tonic-clonic seizure for the first time and a significant increase in seizure frequency. Because of the temporal relation between the seizure worsening and the administration of folic acid, we hypothesize a role of folic acid in provoking seizures, as has been reported in the literature.