COMPARISON OF THE REACTIONS INDUCED BY PSILOCYBIN AND LSD-25 IN MAN BY ISBELL HARRIS

Page 1, number of positive responses at one and one-half hours were calculated and used in constructing the dose-effect curves shown in figure 1.- Analysis of these data at approximately peak effect for both drugs gave potency estimates with 5 per cent confidence limits of 1 mcgm/kg of LSD being equivalent to 121 (103-156) mcgm/kg of psilocybin in the case of pupillary change, and to 110 (60-218) mcgm/kg in the case of responses .on the questionnaire. These two dose-effect curves met the usual t...