The enhancement of .BETA.-lactam antibiotic therapy by novobiocin.

Novobiocin demonstrates an effect similar to that of probenecid (the "probenecid effect") in enhancing the therapeutic efficacy of antibiotics excreted mainly by the renal tubules. The ability of cefoxitin, cephalexin, cephalothin and penicillin G to protect mice against infection with Salmonella schottmuelleri was enhanced 2- to 3-fold when the animals were given oral doses of either probenecid or of novobiocin. The efficacy of cephaloridine, excreted mainly by glomerular filtration, was not enhanced by either probenecid or by novobiocin.