STUDIES ON THE ANTIMICROBIAL EFFECTS OF ANTITUBERCULOUS DRUGS IN VITRO

(4) Synergistic Effects of Antituberculous Drugs Against Tubercle Bacilli in Vitro (Bacteriostatic Effects)

Abstract

1) Out of the combinations of INAH with one of the following drugs, DSM, PAS, TB₁, Vitamin-K, Ceharanthim Protomin, Z-Furan and Neo-Ninophagen-A. T. INAH+DSM, INAH+PAS, INAH+TB₁, INAH+Vitamin-K and INAH+Z-Furan showed synergistic effects. The effects were strongest in INAH+DSM and INAH+Vitamin-K. Combinations of 3 or 4 kinds of these drugs were also effective, and the combination of INAH+DSM+PAS was the most effective one. Combinations of 4 kinds of drugs were not more effective than the cornbinaticns of 3 kinds of drugs.
2) If DSM was added to one of the following dregs, PAS, TB₁, Vitamin-K, Cepharanthin, Protomin, Z-Furan and Neo Minophager-A. T., PAS, TB₁, Vitamin-K, Cepharanthin and Z-Furan groins showed synergistic effects. 4n the contrary, if ore of these drugs were added to DSM, only PAS, TB₁, Vitamin-K, Protomin and Z-Furan groups showed synergistic effects. In any case, DSM-PAS, or PAS-DSM was the most effective one.
Combinations of more than 3 kinds of drugs cut of DSM, INAH, PAS and TBr were effective, however, their antimicrobial activities were not higher than that of DSM+PAS.
3) Among the combinations of PAS with one of the following drugs, TBi, Vitamin-K, Cepharanthin, Protomin, Z-Furan and Neo-Minophagen-A. T., Vitamin-K+PAS and Z-Furan+PAS showed synergistic effects and Neo-Minophagen-A. T.+PAS gave antagonism. The combinations of 3 kinds or 4 kinds of these drugs were effective, and the antimicrobial effects of PAS became highest at PAS+INAH+DSM, however lower effects were obtained at the combinations of 4 drugs.
4) If TB₁ was added to one of the following drugs, Cepharanthin, Protomin, Z-Furan and Neo-Minophagen-A. T. only Z-Furan+TB₁ group showed synergistic effect, while Cepharanthin +TB₁, Protomin+TB₁ and Neo-Minophagen-A. T.+TB₁ showed antagonism, and Vitamin-K+TB₁ showed antagonism even at low density. When TB₁ was added to one of the other drugs, synerid in was observed in Z-Furan₁TB₁ group, meanwhile antagonism was seen in Vitamin-K+TB₁ and Protomin+TB₁ groups and a little synergistic effect was obtained in Cepharanthin+TB₁ at high density and antagonistic effect at thin density. In the combinations of 3 or 4 of TB₁, INAH, DSM and PAS, the antimicrobial action was highest in the combination of 4 kinds of drugs.