Antibacterial Activity of Serum of Normal Subjects after Oral Doses of Demethylchlortetracycline, Chlortetracycline and Oxytetracycline

Abstract

IN a previous paper from this laboratory, Kunin and Finland1 reported that the new tetracycline antibiotic, demethylchlortetracycline, given to normal persons in single or repeated oral doses, produced much higher and better sustained levels of antibacterial activity in the serum than corresponding doses of tetracycline. The superior activity was demonstrated in comparisons employing standard strains of streptococcus, staphylococcus and Bacillus cereus in twofold dilutions of serum in broth, and also by comparison of the concentrations of antibiotic activity in serum as determined by an agar cup-plate diffusion method using B. cereus as the test strain and expressing the results in . . .