Abstract: There have been quite a few papers on the clinical use of L.D.I.A.A., but its thera- peutic action on the depression of the central nervous system in acute poisoning due to barbiturates has not been reported yet. In this paper, acute barbiturate poisoning was induced in mice and observed for the duration of sleep, mortality rate, and the duration of maintainence. Acute barbiturate poisoning was induced also in dogs which were watched for changes in blood pressure and respiration. It shows that in all these animals, L.D.I.A.A. has an action similar to that of picrotoxinum which causes moderate rise of blood pressure, increase of respiration, and more forceful heart beats.