Cefazolin 500mg Injection, USP Single Dose Vial

To reduce the development of drug-resistant bacteria and maintain the effectiveness of Cefazolin Injection, USP and other antibacterial drugs, Cefazolin Injection, USP should be used only to treat or prevent infections that are proven or strongly suspected to be caused by bacteria.

Cefazolin Injection, USP is a sterile semi-synthetic cephalosporin for parenteral administration (Intramuscular or Intravenous). 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.

Structural Formula:

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 date, local epidemiology and susceptibility patters may contribute to the empiric selection of therapy.

Cefazolin for Injection, USP is indicated in the treatment of the following serious infections due to susceptible organisms:

Due to S. pneumoniae, Klebsiella species, Haemophilus influenzae, S. aureus (pennicillin-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 is effective in the eradication of streptococci from the nasopharynx; however, data establishing the efficacy of cefazolin in the subsequent prevention of rheumatic fever are not available at present.

Due to E. coli, P. mirabilis, Klebsiella species and some strains of enterobacter and enterococci.

Due to S. aureus (pennicillin-sensitive and penicillin resistant), S. pyogenes, and other strains of streptococci.

Due to E. coli, various strains of streptococci, P. mirabilis, Klebsiella species and Staphylococcus aureus.

Due to S. aureus.

(i.e., prostatitis, epididymitis) due to E. coli, P. mirabilis, Klebsiella species and some strains of enterococci.

Due to S. pneumoniae, S. aureus (pennicillin-sensitive and penicillin resistant) P. mirabilis, E. coli, and Klebsiella species

Due to S. aureus (pennicillin-sensitive and penicillin resistant), and group A beta hemolytic streptococci.

Appropriate culture and susceptibility studies should be performed to determine susceptibility of the causative organism to cefazolin.

The prophylactic administration of cefazolin 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 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 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 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)

Cefazolin for Injection, USP is contraindicated in patients with known allergy to the cephalosporin group of antibiotics.

Before therapy with Cefazolin Injection, USP is instituted, careful inquiry should be made to determine whether the patient has had previous hypersensitivity reactions to cefazolin, cephalosporins, penicillins, or other drugs. If this product is given to penicillin-sensitive patients, caution should be exercised because cross-hypersensitivity among beta-lactam antibiotics has been clearly documented and may occur in up to 10% of patients with a history of penicillin allergy. If an allergic reaction to Cefazolin Injection, USP occurs, discontinue treatment with the drug. Serious acute hypersensitivity reactions may require treatment with epinephrine and other emergency measures, including oxygen, IV fluids, IV antihistamines, corticosteroids, pressor amines, and airway management, as clinically indicated.

Prolonged use of cefazolin may result in the overgrowth of nonsusceptible organisms. Careful clinical observation of the patient is essential.

Prescribing Cefazolin for Injection, USP is the absence of a proven or strongly suspected bacterial infection of a prophylactic indication is unlikely to provide benefit to the patient and increases the risk of the development of drug-resistant bacteria.

When cefazolin is administered to patients with low urinary output because of impaired renal function, lower daily dosage is required (see DOSAGE AND ADMINISTRATION).

As with other beta-lactam antibiotics, seizures may occur if inappropriately high doses are administered to patients with impaired renal function (see DOSAGE AND ADMINISTRATION).

Cefazolin Injection, USP, as with all cephalosporins, should be prescribed with caution in individuals with a history of gastrointestinal disease, particularly colitis.

Probenecid may decrease renal tubular secretion of cephalosporins when used concurrently, resulting in increased and more prolonged cephalosporin blood levels.

A false positive reaction for glucose in the urine may occur with Benedict’s solution, Fehling’s solution or with CLINITEST® tablets, but not with enzyme-based tests such as CLINISTIX®.

Positive direct and indirect antiglobulin (Coombs) tests have occurred; these may also occur in neonates whose mothers received cephalosporins before delivery.

Mutagenicity studies and long-term studies in animals to determine the carcinogenic potential of cefazolin have not been performed.

Reproduction studies have been performed in rats, mice, and rabbits at doses up to 25 times the human dose and have revealed no evidence of impaired fertility or harm to the fetus due to cefazolin. There are, however, no adequate and well-controlled studies in pregnant women. Because animal reproduction studies are not always predictive of human response, this drug should be used during pregnancy only if clearly needed.

When cefazolin has been administered prior to caesarean section, drug levels in cord blood have been approximately one quarter to one third of maternal drug levels. The drug appears to have no adverse effect on the fetus.

Cefazolin is present in very low concentrations in the milk of nursing mothers. Caution should be exercised when cefazolin is administered to a nursing woman.

Safety and effectiveness for use in premature infants and neonates have not been established. See DOSAGE AND ADMINISTRATION for recommended dosage in pediatric patients older than 1 month.

Patients should be counseled that antibacterial drugs including cefazolin should only be used to treat bacterial infections. They do not treat viral infections (e.g., the common cold). When Cefazolin Injection, USP is prescribed to treat a bacterial infection, patients should be told that although it is common to feel better early in the course of therapy, the medication should be taken exactly as directed. Skipping doses or not completing the full course of therapy may: (1) decrease the effectiveness of the immediate treatment, and (2) increase the likelihood that bacteria will develop resistance and will not be treatable by cefazolin or other antibacterial drugs in the future.

The following reactions have been reported:

Gastrointestinal Diarrhea, oral candidiasis (oral thrush), vomiting, nausea, stomach cramps, anorexia, and pseudomembranous colitis. Onset of pseudomembranous colitis symptoms may occur during or after antibiotic treatment (see WARNINGS). Nausea and vomiting have been reported rarely.

Allergic Anaphylaxis, eosinophilia, itching, drug fever, skin rash, Stevens-Johnson syndrome.

Usual Adult Dosage:

Type of Infection	Dose	Frequency
Moderate to severe infections	500 mg to 1 gram	every 6 to 8 hrs.
Mild infections caused by susceptible gram + cocci	250 mg to 500 mg	every 8 hrs.
Acute, uncomplicated urinary tract infections	1 gram	every 12 hrs.
Pneumococcal pneumonia	500 mg	every 12 hrs
Sever, life-threatening infections (e.g., endocarditis, septicemia)*	1 gram to 1.5 grams	every 6 hrs

Pediatric Dosage Guide
Weight		25 mg/kg/day divided into 3 doses		25 mg/kg/day divided into 4 doses
Lbs	Kg	Approximate single dose mg/q8h	Vol. (mL) needed with dilution of 125 mg/mL	Approximate single dose mg/q6h	Vol. (mL) needed with dilution of 125 mg/mL
10	4.5	40 mg	0.35 mL	30 mg	0.25 mL
20	9.0	75 mg	0.60 mL	55 mg	0.45 mL
30	13.6	115 mg	0.90 mL	85 mg	0.70 mL
40	18.1	150 mg	1.20 mL	115 mg	0.90 mL
50	22.7	190 mg	1.50 mL	140 mg	1.10 mL

Weight		50 mg/kg/day divided into 3 doses		50 mg/kg/day divided into 4 doses
Lbs	Kg	Approximate single dose mg/q8h	Vol. (mL) needed with dilution of 25 mg/mL	Approximate single dose mg/q6h	Vol. (mL) needed with dilution of 225 mg/mL
10	4.5	75 mg	0.35 mL	55 mg	0.25 mL
20	9.0	150 mg	0.70 mL	110 mg	0.50 mL
30	13.6	225 mg	1.00 mL	170 mg	0.75 mL
40	18.1	300 mg	1.35 mL	225 mg	1.00 mL
50	22.7	375 mg	1.70 mL	285 mg	1.25 mL

Vial Size	Amount of diluent	Approximate concentration	Appriximate Available volume
500 mg	2 mL	225 mg/mL	2.2 mL
1 gram	2.5 mL	330 mg/mL	3 mL

Cefazolin Injection, USP is supplied in vials containing cefazolin sodium equivalent to 500 mg or 1 gram cefazolin and in infusion bottles containing cefazolin sodium equivalent to 1 gram cefazolin:

NDC 10019-610-01	500 mg/10 mL vial, Carton of 25 vials
NDC 10019-611-03	1 g/10 mL vial, Carton of 25 vials
NDC 10019-611-01	1 g/100 mL vial, Carton of 10 bottles