“…On the other hand, antihistaminic drugs, besides the inhibitory effect on the acute inflammatory reaction (Halpern, 1953), de crease the fu nctional activity accomplished by the inflammatory cells (lancso, 1947 ;Kato and Gozsy, I956a ;Gozsy and Kato, 1956) . As a consequence, they enhance the rate of evolution of experimental tuber culosis (Gozsy and Kato, 1955) and inhibit the natural defence mechanism of guinea pigs against M. lepraemurium (Kato,I957).…”