The results of the use of barbexaclone (ciclo-hexil-aminopropan) in association with fenil-etil-barbiturate, as a single anticonvulsant drug in a clinical and therapeutic trial are reported. Seventy patients, 36 women and 34 men, 52 children and 18 adults, all of them with two or more epileptic grand-mal seizures at the begining of treatment, were selected. In 53 patients a complete 18 months follow-up observation was performed. In this group of patients, 96% of them were free of seizures during the observation time. In 20 patients the barbiturate plasma concentration was measured. For these patients, the effectiveness of the treatment was up to 89%, in terms of complete control of convulsive crises. The measurements of the plasma level of anticonvulsants has shown to be most useful and a safe therapeutic guide in the treatment of epilepsies.