Thyrotoxic encephalopathy and recurrent seizures.

Epilepsy is a rare but possible manifestation of thyrotoxicosis. The patient reported here developed recurrent, generalized and focal seizures, as presenting symptoms of a thyrotoxic encephalopathy. Intercritic EEG records showed triphasic waves. Seizures and signs of encephalopathy disappeared and the EEG reverted to normal only after treatment of the thyroid hyperfunction. It is concluded that thyroid function should be evaluated in cases of otherwise unexplained encephalopathy with untreatable seizures and triphasic waves.