Central hyperventilation related to administration of topiramate.

Topiramate is a recently released antiepileptic agent used in the treatment of patients with refractory seizure disorders. In addition to its antiepileptogenic activities, it results in inhibition of carbonic anhydrase isoenzymes II and IV, which are present in the central nervous system. A 15-year-old female who presented with hyperpnea and primary respiratory alkalosis is reported. Other possible etiologies of the central hyperventilation syndrome were excluded. The problem resolved within 24 hours after discontinuing topiramate.