Abstract
Methods for estimating minimal lethal doses and for determining duration of action of ouabain, proscillaridin A, α-acetyldigoxin, β-acetyldigoxin, digoxin and digitoxin were investigated in the guinea-pig. The minimal lethal dose of these drugs was estimated by infusion-toxicity in which the optimal infusion time and speed for a maximal utilization of drugs resulted in a minimal value of lethal doses (the method of Kosswig and Engelhardt). Duration of action of these drugs was determined by the method of Rand, Stafford and Thorp. The relationship between the elimination of these drugs and the duration of action provides an estimate for the rates of elimination. The rate of elimination (% LD/min) was 16 for ouabain, 14 for proscillaridin A, 9 for β-acetyldigoxin, 6 for α-acetyldigoxin, 4 for digoxin and 1 for digitoxin.
