nt infections that are proven or strongly suspected to be caused by susceptible bacteria. when culture and susceptibility information are available, they should be considered in selecting or modifying antibacterial therapy. in the absence of such data, local epidemiology and susceptibility patterns may contribute to the empiric selection of therapy.

ent of cdad. hypertoxin producing strains of c. difficile cause increased morbidity and mortality, as these infections can be refractory to antimicrobial therapy and may require colectomy. cdad must be considered in all patients who present with diarrhea following antibiotic use. careful medical history is necessary since cdad has been reported to occur over two months after the administration of antibacterial agents. if cdad is suspected or confirmed, ongoing antibiotic use not directed against c. difficile may need to be discontinued. appropriate fluid and electrolyte management, protein supplementation, antibiotic treatment of c. difficile , and surgical evaluation should be instituted as clinically indicated.

to moderate infections) 50 mg/kg/day im or iv in equally divided doses every 6 hours (mild to moderate infections) 1 gram im or iv every 4 to 6 hours (severe infections) 100 mg/kg/day im or iv in equally divided doses every 4 to 6 hours (severe infections) premature and neonates 25 mg/kg/day im or iv directions for use for intramuscular use: use sterile water for injection, usp. add 5.4 ml to the 1 gram vial and 10.6 ml to the 2 gram vial. shake well until a clear solution is obtained. after reconstitution, vials will contain 250 mg of active drug per 1.5 ml of solution. the reconstituted solution is stable for 3 days at 70° f or for one week under refrigeration (40° f). for direct intravenous use: use sterile water for injection, usp or sodium chloride injection, usp. add 10 ml to the 1 gram vial and 20 ml to the 2 gram vial. withdraw the entire contents and administer slowly over a period of approximately 10 minutes. for administration by intravenous drip: reconstitute as directed above ( for direct intravenous use ) prior to diluting with intravenous solution. stability periods for oxacillin for injection, usp concentration mg / ml sterile water for injection , usp 0 . 9 % sodium chloride injection , usp m / 6 molar sodium lactate solution 5 % dextrose in water 5 % dextrose in 0 . 45 % sodium chloride 10 % invert sugar injection , usp lactated ringers solution room temperature ( 25 ° c ) 10 to 100 4 days 4 days 10 to 30 24 hrs 24 hrs 0.5 to 2 6 hrs 6 hrs 6 hrs refrigeration ( 4 ° c ) 10 to 100 7 days 7 days 10 to 30 4 days 4 days 4 days 4 days 4 days frozen (- 15 ° c ) 50 to 100 30 days 250/1.5 ml 30 days 100 30 days 10 to 100 30 days 30 days 30 days 30 days 30 days stability studies on oxacillin sodium at concentrations of 0.5 mg/ml and 2 mg/ml in various intravenous solutions listed below indicate the drug will lose less than 10% activity at room temperature (70°f) during a 6-hour period. iv solution 5% dextrose in normal saline only those solutions listed above should be used for the intravenous infusion of oxacillin sodium. the concentration of the antibiotic should fall within the range specified. the drug concentration and the rate and volume of the infusion should be adjusted so that the total dose of oxacillin is administered before the drug loses its stability in the solution in use. if another agent is used in conjunction with oxacillin therapy, it should not be physically mixed with oxacillin but should be administered separately. parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration whenever solution and container permit. do not add supplementary medication to oxacillin for injection, usp.

clude urticaria, pruritus, and fever. although laryngeal edema, laryngospasm, and hypotension occasionally occur, fatality is uncommon. delayed allergic reactions to penicillin therapy usually occur after 48 hours and sometimes as late as 2 to 4 weeks after initiation of therapy. manifestations of this type of reaction include serum sickness-like symptoms (i.e, fever, malaise, urticaria, myalgia, arthralgia, abdominal pain) and various skin rashes. nausea, vomiting, diarrhea, stomatitis, black or hairy tongue, and other symptoms of gastrointestinal irritation may occur, especially during oral penicillin therapy. nervous system reactions neurotoxic reactions similar to those observed with penicillin g may occur with large intravenous doses of oxacillin especially with patients with renal insufficiency. urogenital reactions renal tubular damage and interstitial nephritis have been associated with the administration of oxacillin. manifestations of this reaction may include rash, fever, eosinophilia, hematuria, proteinuria, and renal insufficiency. nephropathy induced by penicillins does not appear to be dose-related and is generally reversible upon prompt discontinuation of therapy. gastrointestinal reactions pseudomembranous colitis has been reported with the use of oxacillin. the onset of pseudomembranous colitis symptoms may occur during or after antibiotic treatment (see warnings ). metabolic reactions agranulocytosis, neutropenia, and bone marrow depression have been associated with the use of oxacillin. hepatotoxicity, characterized by fever, nausea, and vomiting associated with abnormal liver function tests, mainly elevated sgot levels, has been associated with the use of oxacillin. to report suspected adverse reactions, contact fda at 1-800-fda-1088 or www.fda.gov/medwatch.

nt administration of probenecid prolongs the elimination of oxacillin and, consequently, increases the serum concentration. intramuscular injections give peak serum levels 30 minutes after injection. a 250 mg dose gives a level of 5.3 mcg/ml while a 500 mg dose peaks at 10.9 mcg/ml. intravenous injection gives a peak about 5 minutes after the injection is completed. slow iv dosing with 500 mg gives a 5 minute peak of 43 mcg/ml with a half-life of 20 to 30 minutes. microbiology mode of action penicillinase-resistant penicillins exert a bactericidal action against penicillin susceptible microorganisms during the state of active multiplication. all penicillins inhibit the biosynthesis of the bacterial cell wall. mechanism of resistance resistance to penicillins may be mediated by destruction of the beta-lactam ring by a beta-lactamase, altered affinity of penicillin for target, or decreased penetration of the antibiotic to reach the target site. cross resistance resistance to oxacillin (or cefoxitin) implies resistance to all other beta-lactam agents, except newer agents with activity against methicillin-resistant staphylococcus aureus. susceptibility test methods for specific information regarding susceptibility test interpretive criteria and associated test methods and quality control standards recognized by fda for this drug, please see: https://www.fda.gov/stic.

er) even as late as two or more months after having taken the last dose of the antibiotic. if this occurs, patients should contact their physician as soon as possible.