Diphenylhydantoin activated seizures

Abstract
Three cases are presented in which seizure frequency increased during therapy with anticonvulsant drugs. All patients showed other evidence of drug toxicity to the central nervous system at the time of the increased seizure activity. The seizures were generally characterized by opisthotonic posturing or grand mal convulsions, or both. Focal neurological signs appeared in Diphenyl-hydantoin (Dilantin) toxicity appears to be the single most important factor in provoking the seizures. Experimental evidence is cited in support of this hypothesis. In each case increased slow-wave activity in the electroencephalogram was a clue to the nature of the disorder. A drug encephalopathy associated with increased seizure activity should be an indication to decrease or eliminate Dilantin.