Urogenital ReactionsRenal tubular damage and interstitial nephritis have been associated infrequently with the administration of oxacillin. Manifestations of this reaction may include rash, fever, eosinophilia, hematuria, proteinuria, and renal insufficiency.

Gastrointestinal ReactionsPseudomembranous 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 ReactionsAgranulocytosis, neutropenia, and bone marrow depression have been associated with the use of methicillin sodium, nafcillin, oxacillin, and cloxacillin. 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 and cloxacillin.
To report SUSPECTED ADVERSE EVENTS, contact FDA at 1-800-FDA-1088 or www.fda.gov.

OVERDOSAGEThe signs and symptoms of oxacillin overdosage are those described in the ADVERSE REACTIONS section. If signs or symptoms occur, discontinue use of the medication, treat symptomatically, and institute appropriate supportive measures.
DOSAGE AND ADMINISTRATIONThe penicillinase-resistant penicillins are available for oral administration and for intramuscular and intravenous injection. The sodium salts of methicillin, oxacillin, and nafcillin may be administered parenterally and the sodium salts of cloxacillin, dicloxacillin, oxacillin, and nafcillin are available for oral use.

Bacteriologic studies to determine the causative organisms and their susceptibility to oxacillin should always be performed. Duration of therapy varies with the type and severity of infection as well as the overall condition of the patient, therefore it should be determined by the clinical and bacteriological response of the patient. In severe staphylococcal infections, therapy with oxacillin should be continued for at least 14 days. Therapy should be continued for at least 48 hours after the patient has become afebrile, asymptomatic, and cultures are negative. The treatment of endocarditis and osteomyelitis may require a longer term of therapy.

Concurrent administration of oxacillin and probenecid increases and prolongs serum penicillin levels. Probenecid decreases the apparent volume of distribution and slows the rate of excretion by competitively inhibiting renal tubular secretion of penicillin. Penicillin-probenecid therapy is generally limited to those infections where very high serum levels of penicillin are necessary.

Oral preparations of the penicillinase-resistant penicillins should not be used as initial therapy in serious, life-threatening infections (See PRECAUTIONS: General). Oral therapy with the penicillinase-resistant penicillins may be used to follow-up the previous use of a parenteral agent as soon as the clinical condition warrants. With intravenous administration, particularly in elderly patients, care should be taken because of the possibility of thrombophlebitis.

Recommended Dosages for Oxacillin Sodium for Injection, USPIn ADD-Vantage® System: For Intravenous Use Only