Antibiotic Potentiation

EISNER et al. (1953) and Gray et al. (1954) demonstrated that certain organic acids and their salts enhanced absorption of tetracycline antibiotics from the gastrointestinal tract of rats, guinea pigs and dogs. It was later shown that this phenomenon was due to a reversal of calcium inhibition of intestinal absorption of the antibiotics by the organic acids (Price et al., 1959a). The effect of dietary calcium content upon serum antibiotic levels in chickens has been elucidated by Price et al. (1959b). The present report concerns experiments on factors which modify the inhibiting effect of calcium upon absorption of oxytetracycline4 (OTC) from the intestine of chickens. These include calcium level per se and differences related to the anionic portion of calcium salts. An exploratory study was made of possible antibiotic potentiating action of certain fatty acids, their calcium salts and natural and modified neutral fats. Experiment 1. This experiment …