DESCRIPTION Oxacillin for injection, USP is a sterile product for intramuscular or intravenous administration. Oxacillin for injection, USP contains oxacillin sodium, a semisynthetic penicillin derived from the penicillin nucleus, 6-aminopenicillanic acid. It is resistant to inactivation by the enzyme penicillinase (beta-lactamase). Each vial contains oxacillin sodium monohydrate equivalent to 1 gram or 2 grams of oxacillin. The sodium content is 64 mg (2.8 mEq) per gram of oxacillin. The product is buffered with 21 mg dibasic sodium phosphate per gram of oxacillin. Oxacillin for injection, USP is white to off white powder and gives a clear solution upon reconstitution. OXACILLIN SODIUM The chemical name of oxacillin sodium is 4-Thia-1-azabicyclo [3.2.0]heptane-2-carboxylic acid, 3,3-dimethyl-6-[[(5-methyl-3-phenyl-4-isoxazolyl) carbonyl] amino]-7-oxo-, monosodium salt, monohydrate, [2S(2α,5α,6β)]. It is resistant to inactivation by the enzyme penicillinase (beta-lactamase). The molecular formula of oxacillin sodium is C 19 H 18 N 3 NaO 5 S•H 2 O. The molecular weight is 441.43. Structure
⚠️ Warnings
WARNINGS Serious and occasionally fatal hypersensitivity (anaphylactic shock with collapse) reactions have occurred in patients receiving penicillin. The incidence of anaphylactic shock in all penicillin-treated patients is between 0.015 and 0.04 percent. Anaphylactic shock resulting in death has occurred in approximately 0.002 percent of the patients treated. When oxacillin therapy is indicated, it should be initiated only after a comprehensive patient drug and allergy history has been obtained. If an allergic reaction occurs, oxacillin should be discontinued and appropriate therapy instituted. Clostridium difficile associated diarrhea (CDAD) has been reported with use of nearly all antibacterial agents, including oxacillin for injection, USP, and may range in severity from mild diarrhea to fatal colitis. Treatment with antibacterial agents alters the normal flora of the colon leading to overgrowth of C. difficile . C. difficile produces toxins A and B which contribute to the development 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.
