tramuscular administration of equal doses (milligrams per kilogram), plasma levels of the oxime produced by toxogonin were four times higher than those produced by pralidoxirne (l, 2). Urinary excretion of both oximes was quite high: 84 % of the dose for toxogonin and 91 of the dose for pralidoxime chlo-Abstract 0 After intravenous administration to humans, the chloride and niethaiiesulfonate salts of pralidoxime were found to have identical pharmacokinetic characteristics. Toxogonin had a much smaller volume of distribution and a lower renal clearance rate. These findings explain the fivefold difference in plasma concentrations after similar doses of toxogonin and pralidoxime. Keyphrases 'J 'Toxogonin-pralidoxime-kinetic comparison after intravenous administration, man 0 Pralidoxime-toxogoninkinetic conipari:con after intravenous administration, man 0 Volume of distribution-rmeview of definitions and interrelationships of various terms [J Anticholinesterase intoxication therapy-kinetic comparison of toxogonin and pralidoxime, intravenous administration, man C] Pyridinium oxinies-kinetic comparison of toxogonin and pralidoxirrie, intravenous administration, man 0 Pharmacokinetics--comparison of toxogonin-pralidoxime, intravenous administration, man. volume of distribution terms reviewed and compared