CEFAZOLIN

Cefazolin for Injection, USP is a semi-synthetic cephalosporin for parenteral administration. It is the sodium salt of 3-{[(5-methyl-1,3,4-­thiadiazol-2-yl)thio]-methyl}-8-oxo-7-[2-(1H-tetrazol-1-yl) acetamido]-5-thia-1-azabicyclo [4.2.0]oct-2-ene-2-carboxylic acid. The molecular formula is C14H13N8NaO4S3 and molecular weight is 476.49. Structural Formula: Each vial contains 48 mg of sodium/1 gram of cefazolin sodium. Cefazolin for Injection, USP is white to off-white crystalline powder, supplied in vials equivalent to 500 mg or 1 gram of cefazolin. Formula1.jpg

Cefazolin for Injection, USP is indicated in the treatment of the following serious infections due to susceptible organisms: Respiratory Tract Infections: Due to S. pneumoniae , Klebsiella species, H. influenzae, S. aureus (penicillin-sensitive and penicillin-resistant), and group A beta-hemolytic streptococci. Injectable benzathine penicillin is considered to be the drug of choice in treatment and prevention of streptococcal infections, including the prophylaxis of rheumatic fever. Cefazolin for Injection is effective in the eradication of streptococci from the nasopharynx; however, data establishing the efficacy of Cefazolin for Injection in the subsequent prevention of rheumatic fever are not available at present. Urinary Tract Infections: Due to E. coli, P. mirabilis, Klebsiella species, and some strains of enterobacter and enterococci. Skin and Skin Structure Infections: Due to S. aureus (penicillin-sensitive and penicillin-resistant), group A beta-hemolytic streptococci, and other strains of streptococci. Biliary Tract Infections: Due to E. coli , various strains of streptococci, P. mirabilis, Klebsiella species, and S. aureus. Bone and Joint Infections: Due to S. aureus. Genital Infections: (i.e., prostatitis, epididymitis) due to E. coli, P. mirabilis, Klebsiella species, and some strains of enterococci. Septicemia: Due to S. pneumoniae, S. aureus (penicillin-sensitive and penicillin-resistant), P. mirabilis, E. coli and Klebsiella species. Endocarditis: Due to S. aureus (penicillin-sensitive and penicillin-resistant) and group A beta-hemolytic streptococci. Perioperative Prophylaxis: The prophylactic administration of Cefazolin for Injection preoperatively, intraoperatively and postoperatively may reduce the incidence of certain postoperative infections in patients undergoing surgical procedures which are classified as contaminated or potentially contaminated (e.g., vaginal hysterectomy, and cholecystectomy in high-risk patients such as those older than 70 years, with acute cholecystitis, obstructive jaundice, or common duct bile stones). The perioperative use of Cefazolin for Injection may also be effective in surgical patients in whom infection at the operative site would present a serious risk (e.g., during open-heart surgery and prosthetic arthroplasty). The prophylactic administration of Cefazolin for Injection should usually be discontinued within a 24 hour period after the surgical procedure. In surgery where the occurrence of infection may be particularly devastating (e.g., open-heart surgery and prosthetic arthroplasty), the prophylactic administration of Cefazolin for Injection may be continued for 3 to 5 days following the completion of surgery. If there are signs of infection, specimens for cultures should be obtained for the identification of the causative organism so that appropriate therapy may be instituted (see DOSAGE AND ADMINISTRATION ). To reduce the development of drug-resistant bacteria and maintain the effectiveness of Cefazolin for Injection, USP and other antibacterial drugs, Cefazolin for Injection, USP should be used only to treat or prevent 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.

Perioperative Prophylactic Use To prevent postoperative infection in contaminated or potentially contaminated surgery, recommended doses are: a. 1 gram IV or IM administered 1/2 hour to 1 hour prior to the start of surgery. b. For lengthy operative procedures (e.g., 2 hours or more), 500 mg to 1 gram IV or IM during surgery (administration modified depending on the duration of the operative procedure). c. 500 mg to 1 gram IV or IM every 6 to 8 hours for 24 hours postoperatively. It is important that (1) the preoperative dose be given just (1/2 to 1 hour) prior to the start of surgery so that adequate antibiotic levels are present in the serum and tissues at the time of initial surgical incision; and (2) Cefazolin for Injection be administered, if necessary, at appropriate intervals during surgery to provide sufficient levels of the antibiotic at the anticipated moments of greatest exposure to infective organisms. In surgery where the occurrence of infection may be particularly devastating (e.g., open-heart surgery and prosthetic arthroplasty), the prophylactic administration of Cefazolin for Injection may be continued for 3 to 5 days following the completion of surgery. Dosage Adjustment for Patients with Reduced Renal Function Cefazolin for Injection may be used in patients with reduced renal function with the following dosage adjustments: Patients with a creatinine clearance of 55 mL/min. or greater or a serum creatinine of 1.5 mg % or less can be given full doses. Patients with creatinine clearance rates of 35 to 54 mL/min. or serum creatinine of 1.6 to 3 mg % can also be given full doses but dosage should be restricted to at least 8 hour intervals. Patients with creatinine clearance rates of 11 to 34 mL/min. or serum creatinine of 3.1 to 4.5 mg % should be given 1/2 the usual dose every 12 hours. Patients with creatinine clearance rates of 10 mL/min. or less or serum creatinine of 4.6 mg % or greater should be given 1/2 the usual dose every 18 to 24 hours. All reduced dosage recommendations apply after an initial loading dose appropriate to the severity of the infection. Patients undergoing peritoneal dialysis: See CLINICAL PHARMACOLOGY . Pediatric Dosage In pediatric patients, a total daily dosage of 25 to 50 mg per kg (approximately 10 to 20 mg per pound) of body weight, divided into 3 or 4 equal doses, is effective for most mild to moderately severe infections. Total daily dosage may be increased to 100 mg per kg (45 mg per pound) of body weight for severe infections. Since safety for use in premature infants and in neonates has not been established, the use of Cefazolin for Injection in these patients is not recommended. In pediatric patients with mild to moderate renal impairment (creatinine clearance of 70 to 40 mL/min.), 60 percent of the normal daily dose given in equally divided doses every 12 hours should be sufficient. In patients with moderate impairment (creatinine clearance of 40 to 20 mL/min.), 25 percent of the normal daily dose given in equally divided doses every 12 hours should be adequate. Pediatric patients with severe renal impairment (creatinine clearance of 20 to 5 mL/min.) may be given 10 percent of the normal daily dose every 24 hours. All dosage recommendations apply after an initial loading dose Image1.jpg Image2.jpg Image3.jpg

Cefazolin for Injection IS CONTRAINDICATED IN PATIENTS WITH KNOWN ALLERGY TO THE CEPHALOSPORIN GROUP OF ANTIBIOTICS.