[Effect of gamma-hydroxybutyrate on EEG pattern in epilepsy. Preliminary report]

Investigations were carried out in 50 patients with epilepsy who had been subjected previously to careful clinical examination. For the investigations the preparation Gamma-OH EGIC was used in doses of 0.03 g/kg of body weight in rapid intravenous injection. The preparation modified rapidly the EEG tracings which were divided into 4 phases: 1) phase of initial resting record, 2) disappearance of alpha rhythm with increase of medium and low-voltage theta rhythm, 3) high-voltage phase resembling sleep activity with prevalence of delta rhythm, 4) phase of desynchronization--return of normal activity. Out of 50 epileptics in 31 cases temporal-lobe epilepsy was present, in 15 the seizures and EEG changes were generalized, in 4 cases focal non-temporal-lobe epilepsy was recognized. Administration of Gamma-OH to epileptics caused in 100% of cases a modification of the initial tracings and in 84% activation of EEG changes mainly with activation of focal slow-wave activity; in cases of minor absence attacks the drug always induced paroksysmal activity. The preparation is safe and non-toxic and may be used in outpatient clinics. It seems that activation of EEG changes in epileptics by Gamma-OH administration may be due to disturbances of the equilibrium between the structures activating and inhibiting the reticular formation of the brain stem and cerebral cortex.