ABSTRACT
Ofloxacin is a new oral antibacterial fluoro-quinolone, endowed with potent bactericidal activity over a very broad bacterial spectrum. Ofloxacin's minimum bactericidal concentration (MBC) proved to be equal to the minimum inhibitory concentration (MIC) even at high inocula or in the presence of human serum with a high bactericidal rate. The effect of the presence of urine was that the bacteria were sensitive to higher drug concentrations, as in the case of other quinolones; these concentrations, however, are easily reached in the urinary tract after a single therapeutic dose in man. Ofloxacin proved to be extremely effective in curing experimental infections induced by both gram-positive and gram-negative pathogens.
Subject(s)
Anti-Bacterial Agents/pharmacology , Bacteria/drug effects , Oxazines/pharmacology , Animals , Drug Evaluation, Preclinical , Drug Resistance, Microbial , Humans , Male , Mice , OfloxacinABSTRACT
The therapeutic activity of ofloxacin, a new oral fluoroquinolone antibacterial agent, was tested in experimental infections in rodents. Its activity was compared with that of nalidixic acid, norfloxacin, amoxicillin and cotrimoxazole in Pseudomonas aeruginosa pyelonephritis in the rat, and with that of amikacin and cefotaxime in Proteus morganii thigh infections in mice. Ofloxacin proved to be more effective than reference drugs, even if parenterally administered, in reducing the bacterial count in muscle, kidney and urine.
Subject(s)
Anti-Infective Agents/therapeutic use , Oxazines/therapeutic use , Proteus Infections/drug therapy , Pseudomonas Infections/drug therapy , Pyelonephritis/drug therapy , Administration, Oral , Agranulocytosis/complications , Animals , Anti-Infective Agents/administration & dosage , Female , Male , Mice , Ofloxacin , Oxazines/administration & dosage , Proteus Infections/complications , RatsABSTRACT
The antibacterial activity and pharmacokinetics of the beta-lactamase-stable cephalosporin cefuroxime and the gram-negative beta-lactamase-susceptible cephalosporin cefazolin were compared in two contrasting infection models in which Proteus morganii 82, which produces chromosomally mediated beta-lactamase, was the pathogen. In the rat paw model, characterized by high numbers of localized bacteria, cefazolin was destroyed at the site of infection and consequently did not produce a therapeutic response. In the mouse intraperitoneal model cefazolin was also inactive, despite peritoneal concentrations being unaffected by high counts of the beta-lactamase-producing P. morganii in the body cavity. In contrast the pharmacokinetics of cefuroxime was unaffected by the presence of the beta-lactamase-producing P. morganii, and good therapeutic responses were seen in both models.
