Epilepsy and IgA deficiency--the effect of sodium valproate.

IgA deficiency (less than 80 IU/ml serum) occurred in 29% of 41 epileptic patients on anticonvulsant therapy. Sodium valproate users had significantly lower mean IgA levels (102 IU/ml) than non-users (151 IU/ml) and had a significantly higher incidence of IgA deficiency (50%) than non-users (16%). The occurrence of IgA deficiency did not appear to be related to age, sex, number of drugs used or to serum anticonvulsant levels.