Studies of drugs in epilepsy cited by author are not evidence based

EDITOR—We were surprised to read Brodie's letter claiming the existence of “hard empirical evidence” to support a mechanistic approach in the management of epilepsy.1 He refers to an unpublished study in which patients with partial seizures resistant to monotherapy with carbamazepine (a sodium channel blocker) were randomised to take additional valproate or vigabatrin (drugs with GABA-ergic mechanisms).2 In those patients who responded to dual therapy, withdrawal of carbamazepine was attempted, with a view to achieving monotherapy with either …