Dosing & Uses
ADULT and PEDIATRIC
Moderate-to-Severe Infections
0.5-1 g IV q6-8hr
Mild Infections With Gram-Positive Cocci
250-500
mg IV q8hr
Mild-to-Moderate Cholecystitis
1-2 g IV q8hr for 4-7 days
Acute Uncomplicated Urinary Tract Infection
1 g IV q12hr
Pneumococcal Pneumonia
500 mg IV q12hr
Severe, Life-threatening Infection
1-1.5 g IV q6hr
Perioperative Prophylaxis
Preoperatively: 1-2 g IV/IM 30-60 minutes before procedure
During surgery for lengthy procedures (ie, >2 hr): 0.5-1 g IV
Postoperatively: 0.5-1 g IV q6-8hr for 24 hr
Surgical infection
- Cardiac procedures, hysterectomy, oral or pharyngeal procedures, craniotomy, joint replacement, thoracic procedures, arterial procedures, amputation, traumatic wounds; high-risk esophageal, gastroduodenal, or biliary tract procedures: 1-2 g IV
- Colorectal procedures: 1-2 g IV plus metronidazole 0.5 g IV
- High-risk cesarean section, 2nd trimester abortion: 1 g IV
- Ophthalmic procedures: 100 mg subconjunctivally
Endocarditis
1 g IV/IM 30-60 minutes before procedure
American Heart Association (AHA) guidelines: Endocarditis prophylaxis recommended only for high-risk patients
Bacterial Keratitis (Off-label)
1 drop instilled into affected eye(s) q1-2hr; typically alternated every other hour with antibiotic providing gram-negative coverage (eg, tobramycin)
Extemporaneous compounded fortified cefazolin 50 mg/mL
- Dilute 500 mg parenteral cefazolin powder in sterile water to form 10 mL solution
- Store refrigerated; preparation expires in 7 days
Dosing Modifications
Renal impairment
- CrCl 35-54 mL/min: Give recommended dose at intervals ≥8hr
- CrCl 11-34 mL/min: Give half of recommended dose q12hr
- CrCl ≤10 mL/min: Give half of recommended dose q18-24hr
Hepatic impairment
- Not studied
Dosing Considerations
Susceptible organisms
- Streptococcus pneumoniae, Klebsiella, Haemophilus influenzae, Staphylococcus aureus, group A beta-hemolytic streptococcus, Escherichia coli, Proteus mirabilis, Enterobacter (some strains)
Infections With Gram-Positive Cocci
Neonates (<28 days)
- <7 days: 40 mg/kg/day IV/IM divided q12hr
- >7 days, <2 kg: 40 mg/kg/day IV/IM divided q12hr
- >7 days, >2 kg: 60 mg/kg/day IV/IM divided q8hr
Infants & children
- 25-100 mg/kg/day IV/IM divided q6-8hr; not to exceed 6 g/day
Endocarditis
Prophylaxis
50 mg/kg IV/IM ≤30-60 minutes before procedure; not to exceed 1 g
AHA guidelines: Endocarditis prophylaxis recommended only for high-risk patients
Community-Acquired Pneumonia
>3 months and children: 150 mg/kg/day IV/IM divided q8hr (moderate to severe infections, methicillin susceptible S aureus preferred
Mild to Moderate Infections
25-50 mg/kg/day IV divided q6-8hr
Severe Infections
May increase to 100 mg/kg/day IV divided q6-8hr
Perioperative Prophylaxis
Aged 10-17 and CrCl ≥70 mL/min
- Preoperatively <50 kg: 1 g IV 30-60 minutes before procedure
- Preoperatively ≥50 kg: 2 g IV 30-60 minutes before procedure
- During surgery for lengthy procedures (ie, >2 hr): 0.5-1 g IV
- Postoperatively: 0.5-1 g IV q6-8 hr for 24 hr
Dosage Modifications
Renal impairment
- CrCl 40-70 mL/min: 60% normal daily dose in equally divided q12hr
- CrCl 20-40 mL/min: 25% normal daily dose in equally divided q12hr
- CrCl 5-20 mL/min: 10% normal daily dose q24hr
Hepatic impairment
- Not studied
Dosing Considerations
Premixed cefazolin
- Premixed cefazolin 1 g/50 mL or 2 g/100 mL 2 g recommended for use in pediatric patients for whom appropriate dosing with this formulation can be achieved
- Use in pediatric patients who require entire contents of 1 or 2 g dose and not any fraction of it
-
Perioperative prophylaxis
- May use in pediatric patients aged 10-17 years for whom appropriate dosing with this formulation can be achieved
Warnings
Contraindications
Documented hypersensitivity
Cautions
Endocarditis prophylaxis recommended only for high-risk patients, per AHA guidelines
Prolonged treatment, hepatic or renal disease, or nutritional deficiency may be associated with increased international normalized ratio (INR)
Use with caution in patients with seizure disorder (high levels are associated with increased risk of seizures); seizures may occur, particularly in patients with renal impairment when dosage is not reduced appropriately; dose must be adjusted in severe renal insufficiency (high doses may cause CNS toxicity); discontinue if seizures occur or make appropriate dosage adjustments in patients with renal impairment; continue anticonvulsant therapy in patients with known seizure disorders
Prescribing cefazolin injection in absence of proven or strongly suspected bacterial infection or a prophylactic indication is unlikely to provide benefit to the patient and increases risk of development of drug-resistant bacteria
As with other antimicrobials, prolonged use of cefazolin injection may result in overgrowth of nonsusceptible microorganisms; repeated evaluation of the patient's condition is essential; should superinfection occur during therapy, appropriate measures should be taken
Therapy may result in a false-positive reaction with glucose in urine when using glucose tests based on Benedict’s copper reduction reaction that determine amount of reducing substances like glucose in urine; it is recommended that glucose tests based on enzymatic glucose oxidase be used
Hypersensitivity reactions, including anaphylaxis, reported with administration of dextrose-containing products; these reactions have been reported in patients receiving high concentrations of dextrose (i.e. 50% dextrose); reactions have been reported when corn-derived dextrose solutions were administered to patients with or without a history of hypersensitivity to corn products
As with other dextrose-containing solutions, cefazolin injection should be prescribed with caution in patients with overt or known subclinical diabetes mellitus or carbohydrate intolerance for any reason
Cefazolin injection may be associated with a fall in prothrombin activity; those at risk include patients with renal or hepatic impairment or poor nutritional state, as well as patients receiving a protracted course of antimicrobial therapy, and patients previously stabilized on anticoagulant therapy; prothrombin time should be monitored in patients at risk and exogenous vitamin K administered as indicated
Antibiotic associated diarrhea
- Clostridioides difficile-associated diarrhea (CDAD) reported with use; may range in severity from mild diarrhea to fatal colitis; treatment with antibacterial agents alters normal flora of colon leading to overgrowth of C. difficile
- C. difficile produces toxins A and B, which contribute to development of CDAD; hypertoxin-producing isolates 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 antibacterial drug use; careful medical history is necessary since CDAD has been reported to occur over two months after administration of antibacterial agents
- If CDAD is suspected or confirmed, ongoing antibacterial drug use not directed against C. difficile may need to be discontinued; appropriate fluid and electrolyte management, protein supplementation, antibacterial drug treatment of C. difficile, and surgical evaluation instituted as clinically indicated
Pregnancy & Lactation
Pregnancy
Available data from published prospective cohort studies, case series and case reports over several decades with cephalosporin use, including cefazolin, in pregnant women have not established a drug-associated risk of major birth defects, miscarriage, or adverse maternal or fetal outcomes; drug crosses the placenta
Animal data
- Animal reproduction studies with rats, mice and rabbits administered cefazolin during organogenesis at doses 1 to 3 times maximum recommended human dose (MRHD) did not demonstrate adverse developmental outcomes; in rats subcutaneously administered cefazolin prior to delivery and throughout lactation, there were no adverse effects on offspring at a dose approximately 2 times the MRHD
Lactation
Data from published literature report that cefazolin is present in human milk, but not expected to accumulate in a breastfed infant; there are no data on effects of drug on breastfed child or on milk production
Developmental and health benefits of breastfeeding should be considered along with mother’s clinical need for therapy and any potential adverse effects on breastfed child from drug or from the mother’s underlying condition
Pregnancy Categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
Adverse Effects
Frequency Not Defined
Anorexia
Diarrhea
Eosinophilia
Fever
Increased transaminases
Leukopenia
Nausea and vomiting
Neutropenia
Oral candidiasis
Pain at injection site
Phlebitis
Pseudomembranous colitis
Seizure
Stevens-Johnson syndrome
Thrombocytopenia
Thrombocytosis
Transient elevation of hepatic enzymes
Vaginitis