THE EFFECT OF 2,2'-PHOSPHINICODILACTIC ACID ON THE ABSORPTION OF TETRACYCLINES WITH NOTES ON PHARMACOLOGY AND TOXICITY

¹ Experimental Therapeutics Research Section, Lederle Laboratories, American Cyanamid Company, Pearl River, New York

Screening for substances which would increase the absorption of orally administered tetracydines, as reflected by serum concentrations of the antibiotics, has resulted in the discovery of a highly effective substance, namely: 2, 2'-phosphinicodilactic acid (phoscolic acid). This compound demonstrably increases the serum concentrations of coadministered tetracvclines in the rat and dog.

On the basis of acute toxicity studies in mice and of short-term feeding experiments with rats and dogs, phoscolic acid appears to be relatively nontoxic.

When tested at the indicated doses in our standard screening procedures, phoscolic acid showed neither antibacterial, antineoplastic, analgesic, hypoglycemic, antidepressant, depressant nor diuretic effects.

Improper storage of the phoscolic acid-tetracycline mixture results in the formation of tetracycline degradation products.