1.The amebicidal potential of each of 10 drugs was evaluated by a newly developed method for demonstrating the direct amebicidal activity of various drugs in vitro.
2.Penicillin G, streptomycin, Chloromycetin, and bacitracin each exhibited a very low amebicidal potential whereas Aureomycin, terramycin, and Simaroubidin each exhibited a very high potential even in very low concentrations. Emetine HCl, actidione, and arsenamide sodium each exhibited remarkable amebicidal activity but their value as therapeutic agents is subject to unfavorable data concerning their toxicity.
3.The advantage of ameba-trypanosome cultures over ameba-bacteria cultures for the screening of drugs was demonstrated since the trypanosome associates were apparently unaffected by the drugs.
4.The value of the test-system was emphasized by the high degree of correlation between the results reported herein and the results previously reported from the testing of many of the same drugs in human cases of amebiasis.
5.The method is offered as a procedure for selecting from the large number of new drugs those of high amebicidal potential for more advanced studies in the treatment of amebiasis.
Federal Security Agency, Public Health Service, National Institutes of Health, National Microbiological Institute (Laboratory of Tropical Diseases), Bethesda, Maryland.