TY - JOUR T1 - BIOLOGICAL COMPARISON OF LOCAL ANAESTHETICS JF - Journal of Pharmacology and Experimental Therapeutics JO - J Pharmacol Exp Ther SP - 78 LP - 84 VL - 85 IS - 1 AU - EDITH BÜLBRING AU - ISABELLA WAJDA Y1 - 1945/09/01 UR - http://jpet.aspetjournals.org/content/85/1/78.abstract N2 - 1. Two methods are described for testing the potency of local anaesthetics. 2. With a certain range of concentrations a linear relationship exists between the logarithm of the concentration of the local anaesthetics which were examined and the time at which plexus anaesthesia in frogs develops. 3. When the intracutaneous wheal in guinea-pigs is used, a similar linear relation exists between the logarithm of the concentration of the local anaesthetic and an index expressing both intensity and duration of anaesthesia. 4. The lines for β-eucaine, procaine and nupercaine, though parallel to each other, are not parallel to that for cocaine. It is suggested, therefore, to use procaine as a standard of comparison. It was observed that when adrenaline was added to procaine and the mixture was compared with cocaine by the guinea-pig method, the log dose-effect lines became parallel. ER -