Trimethadione in doses of 200-400 mg/kg restores the normal electroencephalogram after the production of grand-mal-like electrical patterns in rabbits by DFP. Trimethadione when administered before DFP prevents the establishment of the seizure pattern, though not of milder types of excessive activity. A profound fall of cholinesterase activity is observed, and presumably acetylcholine accumulates. Despite its valuable therapeutic effects trimethadione does not hinder the extreme decrease of cholinesterase activity.Atropine, like trimethadione, both prevents the electrical seizures and restores the control electroencephalogram after the abnormal brain waves have been evoked by DFP, and yet the cholinesterase activity is also greatly diminished and to the same extent as it is in the absence of atropine. Pentothal has been used successfully to restore the normal electroencephalogram after seizure patterns have been produced. Phenobarbital possesses both preventive and curative effects while dilantin has been used only to keep the convulsive pattern from occuring. Like trimethadione, however, dilantin permits some excessive electrical activity.Abstract Teaser