Neurology · 1984 · 25 citations · 0 references
MedicinePharmacologyPharmacotherapyClinical PharmacologyEpilepsyNeuropharmacologyAntiepileptic Drug MonitoringAntiepileptic PharmacologyAntiepileptic PharmacotherapySeizure ManagementAntiepileptic Clinical TrialsAntiepileptic Drug SafetyBlood Sampling From Venous LinesValproate PharmacologyValproic Acid
Valproic acid (VPA) was given to 24 epileptic patients who were already being treated with other antiepileptic drugs. A standardized loading dose of VPA was administered, and venous blood was sampled at 0, 1, 2, 3, and 4 hours. Ammonia (NH3) was higher in patients who, during continuous therapy, complained of drowsiness (7 patients) than in those who were symptom-free (17 patients), although VPA plasma levels were similar in both groups. By measuring VPA-induced changes of blood NH3 content, it may be possible to identify patients at higher risk of obtundation when VPA is given chronically.