[Changes of the pain threshold induced by analgetic drugs (author's transl)].

In two groups (i.v. and p.o. application) of 6 healthy subjects we tested the changes of the individual pain threshold induced by Flupirtine, Pentazocin and placebo under double blind conditions. The experimental pain was caused by radiant heat for isolated C-fiber-stimulation. The results of p.o. application showed an average increase of the pain threshold of +1,27 degrees C by Flupirtine, +0,81 by Pentazocin, and a slight decrease of -0,68 degrees C by placebo. The figures under i.v. application were +2,04 degrees C for Flupirtine, +1,01 degrees C for Pentazocin and +0,16 degrees C for placebo.