RT Journal Article SR Electronic T1 THE EFFECTS OF DFP ON THE CONVULSANT DOSE OF THEOPHYLLINE, THEOPHYLLINE-ETHYLENEDIAMINE AND 8-CHLOROTHEOPHYLLINE JF Journal of Pharmacology and Experimental Therapeutics JO J Pharmacol Exp Ther FD American Society for Pharmacology and Experimental Therapeutics SP 237 OP 242 VO 101 IS 2 A1 Johns, R. J. A1 Bales, P. D. A1 Himwich, H. E. YR 1951 UL http://jpet.aspetjournals.org/content/101/2/237.abstract AB 1. Theophylline and theophylline-ethylenediamine produce cortical seizures in dosages which are comparable on a basis of theophylline content. 2. The amount of theophylline and theophylline-ethylenediamine required to produce cortical seizures was reduced to one-sixth by the prior administration of DFP. 3. In most cases (and possibly in all cases) this synergism was not due to the anti-cholinesterase activity of the theophylline-ethylenediamine. 4. Theophylline and theophylline-ethylenediamine are not recommended in the treatment of bronchospasm produced by anticholinesterase poisoning because of the danger of precipitating convulsions. The data were obtained in rabbits and may apply to man as well. 5. 8-Chlorotheophylline did not produce cortical seizures. 6. After subconvulsant doses of DFP, 8-chlorotheophylline still failed to produce seizures in nine out of ten experiments.