Class: First Generation Cephalosporins
CAS Number: 27164-46-1
Brands: Ancef
Introduction
Antibacterial; β-lactam antibiotic; first generation cephalosporin.100 115 116 117 119 a
Uses for Cefazolin Sodium
Biliary Tract Infections
Treatment of biliary tract infections caused by susceptible Escherichia coli,100 115 116 117 119 Klebsiella,115 116 Proteus mirabilis,100 115 116 117 119 Staphylococcus aureus,100 115 116 117 119 or various streptococci.100 115 116 117 119
Bone and Joint Infections
Treatment of bone and joint infections caused by susceptible S. aureus.100 115 116 117 119
Endocarditis
Treatment of endocarditis caused by susceptible Streptococcus pyogenes.100 113 114 115 116 117 119 AHA recommends cefazolin as an alternative for treatment of staphylococcal endocarditis113 114 or endocarditis caused by viridans streptococci†, S. bovis†, S. pneumoniae†, S. pyogenes, or groups B, C, and G streptococci† in penicillin-allergic individuals; should not be used in those with immediate-type penicillin hypersensitivity (see Cross-hypersensitivity under Cautions).113
Alternative for prevention of α-hemolytic (viridans group) streptococcal endocarditis† in individuals undergoing certain dental or upper respiratory tract procedures who have cardiac conditions that put them at highest risk.104 Oral amoxicillin is usual drug of choice for such prophylaxis;104 cefazolin (or ceftriaxone) is an alternative in penicillin-allergic individuals or when an oral anti-infective cannot be used.104 Should not be used in those with immediate-type penicillin hypersensitivity (see Cross-hypersensitivity under Cautions).104 Consult most recent AHA recommendations for specific information on which cardiac conditions are associated with highest risk of endocarditis and which procedures require prophylaxis.104
Respiratory Tract Infections
Treatment of respiratory infections caused by susceptible S. pneumoniae,100 115 116 117 119 S. pyogenes (group A β-hemolytic streptococci),100 115 116 117 119 S. aureus (including penicillin-resistant strains),100 115 116 117 119 Klebsiella,115 116 or Haemophilus influenzae.115 116
Septicemia
Treatment of septicemia caused by susceptible S. pneumoniae,100 115 116 117 119 S. aureus (including penicillinase-producing strains),100 115 116 117 119 E. coli,100 115 116 117 119 Klebsiella,115 116 or P. mirabilis.100 115 116 117 119
Skin and Skin Structure Infections
Treatment of skin and skin structure infections caused by susceptible S. aureus (including penicillinase-producing strains),100 115 116 117 119 S. pyogenes,100 115 116 117 119 or other streptococci.100 115 116 117 119
Urinary Tract Infections (UTIs) and Urogenital Infections
Treatment of UTIs caused by susceptible E. coli,100 115 116 117 119 P. mirabilis,115 116 117 119 Klebsiella,115 116 some strains of Enterobacter,115 116 or some strains of enterococci.115 116
Treatment of prostatitis or epididymitis caused by susceptible E. coli,100 115 116 117 119 Klebsiella,115 116 P. mirabilis,100 115 116 117 115 116 119 or some strains of enterococci.115 116
Prevention of Perinatal Group B Streptococcal Disease
Alternative to penicillin G or ampicillin for prevention of perinatal group B streptococcal (GBS) disease† (early-onset neonatal GBS disease) in penicillin-allergic pregnant women who do not have immediate-type penicillin hypersensitivity (see Cross Hypersensitivity under Cautions).111
Intrapartum anti-infective prophylaxis to prevent early-onset neonatal GBS disease is administered to women identified as GBS carriers during routine prenatal GBS screening performed at 35–37 weeks during the current pregnancy and to women who have GBS bacteriuria during the current pregnancy, a previous infant with invasive GBS disease, unknown GBS status with delivery at <37 weeks gestation, amniotic membrane rupture for ≥18 hours, or intrapartum temperature of ≥38°C.111 112
Perioperative Prophylaxis
Perioperative prophylaxis in patients undergoing surgical procedures classified as contaminated or potentially contaminated (e.g., vaginal hysterectomy, high-risk cesarean section, cholecystectomy in high-risk patients) and in those undergoing surgical procedures in which the development of infection at the surgical site would represent a serious risk (e.g., cardiac surgery, prosthetic arthroplasty).100 102 106 107 108 109 110 115 116 117 119
Drug of choice for perioperative prophylaxis for a variety of procedures, including cardiac, noncardiac thoracic, esophageal, gastroduodenal, biliary tract, gynecologic and obstetric, head and neck, neurologic, orthopedic, and vascular surgery.102 106
A drug or regimen with activity against anaerobic bacteria is recommended for procedures that might involve exposure to Bacteroides fragilis or other anaerobic bowel bacteria (e.g., colorectal surgery, appendectomy).102 106 Cefoxitin and cefotetan are more active than cefazolin against these bacteria; alternatively, metronidazole can be used in conjunction with cefazolin to provide anaerobic coverage.102 106
Cefazolin Sodium Dosage and Administration
Administration
Administer by IV injection or infusion or by deep IM injection.100 115 116 117 119
IV Injection
Reconstitution and Dilution
Reconstitute vials containing 500 mg or 1 g of cefazolin with 2 or 2.5 mL, respectively, of sterile water for injection to provide solutions containing approximately 225 or 330 mg/mL, respectively.100 115 Then further dilute reconstituted solution in approximately 5 mL of sterile water for injection.100 115
Rate of Administration
Inject directly into a vein over a period of 3–5 minutes or slowly into the tubing of a freely flowing compatible IV solution.100 115
IV Infusion
Reconstitution and Dilution
Reconstitute vials containing 500 mg or 1 g of cefazolin with 2 or 2.5 mL, respectively, of sterile water for injection to provide solutions containing approximately 225 or 330 mg/mL, respectively.100 115 Then further dilute reconstituted solution in 50–100 mL of a compatible IV solution.100 115
Reconstitute 10- or 20-g pharmacy bulk packages according to the manufacturers' directions and then further dilute in a compatible IV solution prior to IV infusion.100 116
Reconstitute (activate) commercially available Duplex drug delivery system containing 1 or 2 g of lyophilized cefazolin and 50 mL of dextrose injection in separate chambers according to the manufacturer's directions.117
Thaw the commercially available premixed injection (frozen) at room temperature (25°C) or under refrigeration (5°C); do not thaw by immersion in a water bath or by exposure to microwave radiation.119 A precipitate may have formed in the frozen injection, but should dissolve with little or no agitation after reaching room temperature.119 Discard thawed injection if solution is cloudy or contains an insoluble precipitate or if container seals or outlet ports are not intact or leaks are found.119 Do not use in series connections with other plastic containers, since such use could result in air embolism from residual air being drawn from the primary container before administration of fluid from the secondary container is complete.119
IM Injection
Inject IM deeply into a large muscle mass.100 115
Reconstitution
Reconstitute vials containing 500 mg or 1 g of cefazolin with 2 or 2.5 mL, respectively, of sterile water for injection to provide solutions containing approximately 225 or 330 mg/mL, respectively.100 115 Shake well until dissolved.100 115
Dosage
Available as cefazolin sodium; dosage expressed in terms of cefazolin.100 115 116 117 119
Pediatric Patients
Mild to Moderately Severe Infections
IV or IM
Children >1 month of age: 25–50 mg/kg daily in 3 or 4 equally divided doses.100 105 115 116 119
Severe Infections
IV
Children >1 month of age: 50–100 mg/kg daily in 3 or 4 equally divided doses.100 105 115 116 119
Endocarditis
Treatment of Staphylococcal Endocarditis
IV
100 mg/kg daily (up to 6 g daily) in 3 or 4 equally divided doses.114
For native valve endocarditis, duration of treatment is 6 weeks (with or without gentamicin given during the first 3–5 days).113 114
For endocarditis involving prosthetic valves or other prosthetic materials, duration of treatment is ≥6 weeks (with or without rifampin given for ≥6 weeks).114
Prevention of Endocarditis in Patients Undergoing Certain Dental or Respiratory Tract Procedures†
IV or IM
A single dose of 50 mg/kg given 0.5–1 hour prior to the procedure.104
Perioperative Prophylaxis
Cardiac or Cardiothoracic Surgery
IV
20–30 mg/kg given at induction of anesthesia (within 0.5–1 hour prior to incision).103 Some clinicians suggest additional doses of 20–30 mg/kg every 8 hours for up to 72 hours; most clinicians state postoperative doses usually unnecessary and may increase risk of bacterial resistance.102 106 110
Neurosurgery
IV
20–30 mg/kg given at induction of anesthesia (within 0.5–1 hour prior to incision).103
Head and Neck Surgery
IV
20–30 mg/kg given at induction of anesthesia (within 0.5–1 hour prior to incision) for clean head and neck surgery with placement of prosthesis.103 For clean-contaminated head and neck surgery involving incision through oral or pharyngeal mucosa, 30–40 mg/kg at induction of anesthesia.103
GI, Pancreatic, or Biliary Tract Surgery
IV
20–30 mg/kg given at induction of anesthesia (within 0.5–1 hour prior to incision).103
Vascular or Orthopedic Surgery
IV
20–30 mg/kg given at induction of anesthesia (within 0.5–1 hour prior to incision).103 Some clinicians suggest additional doses of 20–30 mg/kg every 8 hours for up to 24 hours; most clinicians state postoperative doses usually unnecessary and may increase risk of bacterial resistance.102 106 110
Adults
Mild Infections Caused by Gram-positive Bacteria
IV or IM
250–500 mg every 8 hours.100 115 116 117 119
Moderate to Severe Infections
IV or IM
500 mg–1 g every 6–8 hours.100 115 116 117 119
Severe, Life-threatening Infections
IV or IM
1–1.5 g every 6 hours.100 115 116 117 119 Dosage up to 12 g daily has been used.100 115 116 117 119
Endocarditis
Treatment of Endocarditis
IV or IM
1–1.5 g every 6 hours.100 115 116 117 119 Dosage up to 12 g daily has been used.100 115 116 117 119
AHA recommends 2 g IV every 8 hours for 4–6 weeks for native valve staphylococcal endocarditis (with or without gentamicin during the first 3–5 days).113
Prevention of Endocarditis in Patients Undergoing Certain Dental or Upper Respiratory Tract Procedures†
IV or IM
A single 1-g dose given 0.5–1 hour prior to the procedure.104
Respiratory Tract Infections
Pneumococcal Pneumonia
IV or IM
500 mg every 12 hours.100 115 116 117 119
Septicemia
IV or IM
1–1.5 g every 6 hours.100 115 116 117 119 Doses up to 12 g daily have been used.100 115 116 117 119
Urinary Tract Infections (UTIs)
Acute Uncomplicated Infections
IV or IM
1 g every 12 hours.100 115 116 117 119
Prevention of Perinatal Group B Streptococcal (GBS) Disease†
IV
An initial 2-g dose (at time of labor or rupture of membranes) followed by 1 g every 8 hours until delivery.111
Perioperative Prophylaxis
General Adult Dosage
IV or IM
Manufacturers recommend 1 g given 0.5–1 hour prior to surgery; 0.5–1 g during surgery for lengthy procedures (e.g., ≥2 hours); and 0.5–1 g every 6–8 hours for 24 hours postoperatively.100 115 116 117 119 Manufacturers also recommend that prophylaxis be continued for 3–5 days following surgery where the occurrence of infection may be particularly devastating (e.g., open-heart surgery, prosthetic arthroplasty).100 115 116 117 119
Most clinicians recommend 1–2 g given within 60 minutes of initial incision and, if surgery is >4 hours or major blood loss occurs, additional intraoperative doses given every 4–8 hours.102 Postoperative doses usually unnecessary and may increase risk of bacterial resistance.102 106
Cardiac, Cardiothoracic, or Noncardiac Thoracic Surgery.
IV
1–2 g given at induction of anesthesia (within 0.5–1 hour prior to incision).102 103
In patients undergoing open-heart surgery, some experts recommend an additional dose when the patient is removed from bypass.102
For cardiothoracic surgery and heart and/or lung transplantation, some experts suggest additional 1-g doses every 8 hours for up to 48–72 hours; others state that prophylaxis for ≤24 hours is appropriate.103 There is no evidence to support continuing prophylaxis until chest and mediastinal drainage tubes are removed.103
Neurosurgery or Head and Neck Surgery
IV
1–2 g given at induction of anesthesia (within 0.5–1 hour prior to incision).102 103
For clean, contaminated head and neck surgery, some experts suggest 2 g given at induction of anesthesia and every 8 hours for 24 hours.103
GI, Gastroduodenal, Colorectal, Pancreatic, or Biliary Tract Surgery
IV
1–2 g given at induction of anesthesia (within 0.5–1 hour prior to incision).102 103
For colorectal surgery, use in conjunction with IV metronidazole.102
Vascular or Orthopedic Surgery
IV
1–2 g given at induction of anesthesia (within 0.5–1 hour prior to incision).102 103
Some experts suggest additional 1-g doses every 8 hours for up to 24 hours.103
Gynecologic and Obstetric Surgery
IV
1–2 g given at induction of anesthesia (within 0.5–1 hour prior to incision) for hysterectomy or as soon as umbilical cord is clamped for cesarean section.102 103
Special Populations
Hepatic Impairment
No dosage recommendations.100 115 116 117 119
Renal Impairment
Dosage adjustments recommended in patients with Clcr <55 mL/minute.100 115 116 117 119
Administer an initial loading dose appropriate for the severity of the infection, followed by dosage based on the degree of renal impairment.100 115 116 117 119
Dosage for Adults with Renal Impairment100115116117119
Clcr (mL/minute)
|
Dose
|
Frequency
|
|---|
35–54
|
Full dose
|
≥8-hour intervals
|
11–34
|
50% of usual dose
|
Every 12 hours
|
≤10
|
50% of usual dose
|
Every 18–24 hours
|
Dosage for Children >1 Month of Age with Renal Impairment100115116119
Clcr (mL/minute)
|
Dose
|
Frequency
|
|---|
40–70
|
60% of usual dose
|
Every 12 hours
|
20–40
|
25% of usual dose
|
Every 12 hours
|
5–20
|
10% of usual dose
|
Every 24 hours
|
Cautions for Cefazolin Sodium
Contraindications
Known hypersensitivity to cefazolin or other cephalosporins.100 115 116 117 119
Hypersensitivity to corn or corn products: Duplex delivery system containing lyophilized cefazolin and dextrose injection117 and premixed injection (frozen) containing cefazolin in dextrose injection.119
Warnings/Precautions
Warnings
Superinfection/Clostridium difficile-associated Diarrhea and Colitis
Possible emergence and overgrowth of nonsusceptible organisms, especially Enterobacter, Pseudomonas, enterococci, or Candida.a Careful observation of the patient is essential.100 115 116 117 119 Institute appropriate therapy if superinfection occurs.100 115 116 117 119
Treatment with anti-infectives may permit overgrowth of Clostridium difficile.100 115 116 117 119 C. difficile-associated diarrhea and colitis (CDAD; also known as antibiotic-associated diarrhea and colitis or pseudomembranous colitis) has been reported with nearly all anti-infectives, including cefazolin, and may range in severity from mild diarrhea to fatal colitis.100 117 119
Consider CDAD if diarrhea develops during or after therapy and manage accordingly.100 117 119 Careful medical history is necessary since CDAD has been reported to occur as late as 2 months or longer after anti-infective therapy is discontinued.117 119
If CDAD is suspected or confirmed, anti-infective therapy not directed against C. difficile may need to be discontinued.117 119 Some mild cases may respond to discontinuance alone.100 a Manage moderate to severe cases with fluid, electrolyte, and protein supplementation, anti-infective therapy active against C. difficile (e.g., oral metronidazole or vancomycin), and surgical evaluation when clinically indicated.100 117 119
Sensitivity Reactions
Hypersensitivity Reactions
Possible hypersensitivity reactions such as urticaria, pruritus, rash (maculopapular, erythematous, morbilliform), fever and chills, eosinophilia, joint pain or inflammation, edema, erythema, genital and anal pruritus, angioedema, shock, hypotension, vasodilatation, Stevens-Johnson syndrome, erythema multiforme, toxic epidermal necrolysis, exfoliative dermatitis, and anaphylaxis.a
If an allergic reaction occurs, discontinue cefazolin and institute appropriate therapy as indicated (e.g., epinephrine, corticosteroids, and maintenance of an adequate airway and oxygen).100 a
Cross-hypersensitivity
Partial cross-sensitivity among cephalosporins and other β-lactam antibiotics, including penicillins and cephamycins.100 a
Prior to initiation of therapy, make careful inquiry concerning previous hypersensitivity reactions to cephalosporins, penicillins, or other drugs.100 Cautious use recommended in individuals hypersensitive to penicillins:100 avoid use in those who have had an immediate-type (anaphylactic) hypersensitivity reaction and administer with caution in those who have had a delayed-type (e.g., rash, fever, eosinophilia) reaction.a
General Precautions
History of GI Disease
Use with caution in those with a history of GI disease, particularly colitis.100 a (See Superinfection/Clostridium difficile-associated Diarrhea and Colitis under Cautions.)
Prolonged PT
Prolonged PT reported with some cephalosporins.100
Monitor PT in patients at risk, including those with renal or hepatic impairment, poor nutritional state, receiving prolonged therapy, or stabilized on anticoagulant therapy.100 Administer vitamin K when indicated.100
Selection and Use of Anti-infectives
To reduce development of drug-resistant bacteria and maintain effectiveness of cefazolin and other antibacterials, use only for treatment or prevention of infections proven or strongly suspected to be caused by susceptible bacteria.100
When selecting or modifying anti-infective therapy, use results of culture and in vitro susceptibility testing.100 In the absence of such data, consider local epidemiology and susceptibility patterns when selecting anti-infectives for empiric therapy.100
Patients with Diabetes
The commercially available Duplex delivery system containing 1 g of lyophilized cefazolin and 50 mL of dextrose 4% injection should be used with caution in patients with overt or known subclinical diabetes mellitus or in patients with carbohydrate intolerance for any reason.117
Sodium Content
Contains approximately 48 mg (2 mEq) of sodium per g of cefazolin.100 115 116 117
Specific Populations
Pregnancy
Category B.100 115 116 117 119
Lactation
Distributed into milk;100 115 116 117 119 use with caution.100 115 116 117 119
Pediatric Use
Safety and efficacy not established in premature infants or neonates ≤1 month of age.100 115 116 119
Geriatric Use
No overall differences in safety and efficacy in those ≥65 years of age compared with younger adults, but the possibility of increased sensitivity in some geriatric individuals cannot be ruled out.115 116 117 119
Substantially eliminated by kidneys; risk of toxicity may be greater in those with impaired renal function.115 116 117 119 Select dosage with caution and consider monitoring renal function because of age-related decreases in renal function.115 116 117 119 (See Renal Impairment under Dosage and Administration.)
Renal Impairment
Possible increased serum concentrations and serum half-life.a
Possibility of seizures if inappropriately high dosage used in patients with impaired renal function.100 115 116 117 119
Use with caution and reduce dosage.100 115 116 117 119 (See Renal Impairment under Dosage and Administration.)
Common Adverse Effects
GI effects (diarrhea, nausea, vomiting, stomach cramps, oral candidiasis),115 116 117 119 hypersensitivity reactions.115 116 117 119
Interactions for Cefazolin Sodium
Specific Drugs and Laboratory Tests
Drug
|
Interaction
|
Comments
|
|---|
Nephrotoxic Drugs
|
Potential for increased risk of nephrotoxicitya
|
Avoid concomitant use of nephrotoxic agents (e.g., aminoglycosides, colistin, polymyxin B, vancomycin) if possiblea
|
Probenecid
|
Decreased renal clearance and increased concentrations of cefazolin100
|
|
Tests for glucose
|
Possible false-positive reactions in urine glucose tests using Clinitest, Benedict’s solution, or Fehling’s solution100
|
Use glucose tests based on enzymatic glucose oxidase reactions (e.g., Clinistix)100
|
Cefazolin Sodium Pharmacokinetics
Absorption
Bioavailability
Not appreciably absorbed from GI tract; must be administered parenterally.100
After IM injection, peak serum concentrations attained within 1–2 hours.a
Distribution
Extent
Widely distributed into tissues and fluids,a including synovial fluid.100
Only low concentrations distribute into CSF.a
Crosses the placenta100 and is distributed into milk.100
Plasma Protein Binding
74–86%.a
Elimination
Metabolism
Not appreciably metabolized.a
Elimination Route
Excreted unchanged in urine.100 Approximately 60% of a dose excreted within 6 hours and 70–80% excreted within 24 hours in those with normal renal impairment.100
Half-life
Serum half-life approximately 1.8 hours after IV administration and 2 hours after IM administration.100
Special Populations
Half-life increased in renal impairment.100
Stability
Storage
Parenteral
Powder for Injection or IV Infusion
20–25°C;100 115 116 protect from light.100 115 116
Powder and reconstituted solutions may darken; does not indicate loss of potency.100 115 117
Reconstituted solutions containing 225 or 330 mg of cefazolin per mL prepared using sterile or bacteriostatic water for injection or sodium chloride injection are stable for 24 hours at room temperature or 10 days at 5°C.100 115
Store commercially available Duplex drug delivery system containing 1 or 2 g of lyophilized cefazolin and 50 mL of dextrose injection at 20–25°C (may be exposed to 15–30°C).117 Following reconstitution (activation), use within 24 hours if stored at room temperature or within 7 days if stored in a refrigerator; do not freeze.117
Injection (Frozen) for IV Infusion
-20°C or lower.119 Thawed solutions stable for 48 hours when stored at room temperature (25°C) or 30 days under refrigeration (5°C).119
Do not refreeze after thawing.119
Compatibility
For information on systemic interactions resulting from concomitant use, see Interactions.
Parenteral
Solution Compatibility
Compatible
|
|---|
Amino acids 4.25%, dextrose 25%b
|
Dextrose 5 or 10%100 b
|
Dextrose 5% in Ringer’s injection, lactated100 b
|
Dextrose 5% in sodium chloride 0.2, 0.45, or 0.9%100
|
Ionosol B in dextrose 5% in waterb
|
Normosol M in dextrose 5% in waterb
|
Plasma-Lyte in dextrose 5% in waterb
|
Ringer’s injection, lactated100 b
|
Sodium bicarbonate 5%100
|
Sodium chloride 0.9%100 b
|
Drug Compatibility
Admixture Compatibilityb
Compatible
|
|---|
Aztreonam
|
Clindamycin phosphate
|
Famotidine
|
Fluconazole
|
Linezolid
|
Meperidine HCl
|
Metronidazole
|
Metronidazole HCl with sodium bicarbonate
|
Verapamil HCl
|
Incompatible
|
|---|
Amikacin sulfate
|
Atracurium besylate
|
Bleomycin sulfate
|
Clindamycin phosphate with gentamicin sulfate
|
Ranitidine HCl
|
Variable
|
|---|
Cimetidine HCl
|
Y-Site Compatibilityb
Compatible
|
|---|
Acyclovir sodium
|
Allopurinol sodium
|
Amifostine
|
Atracurium besylate
|
Aztreonam
|
Bivalirudin
|
Calcium gluconate
|
Cefpirome sulfate
|
Cyclophosphamide
|
Dexmedetomidine HCl
|
Diltiazem HCl
|
Docetaxel
|
Doxapram HCl
|
Doxorubicin HCl liposome injection
|
Enalaprilat
|
Esmolol HCl
|
Etoposide phosphate
|
Famotidine
|
Fenoldopam mesylate
|
Filgrastim
|
Fluconazole
|
Fludarabine phosphate
|
Foscarnet sodium
|
Gatifloxacin
|
Gemcitabine HCl
|
Granisetron HCl
|
Heparin sodium
|
Hetastarch in lactated electrolyte injection (Hextend)
|
Insulin, regular
|
Labetalol HCl
|
Lidocaine HCl
|
Linezolid
|
Magnesium sulfate
|
Melphalan HCl
|
Meperidine HCl
|
Midazolam HCl
|
Milrinone lactate
|
Morphine sulfate
|
Multivitamins
|
Nicardipine HCl
|
Ondansetron HCl
|
Pancuronium bromide
|
Perphenazine
|
Propofol
|
Ranitidine HCl
|
Remifentanil HCl
|
Sargramostim
|
Tacrolimus
|
Teniposide
|
Theophylline
|
Thiotepa
|
Vecuronium bromide
|
Vitamin B complex with C (Berocca-C and Berocca-C 500)
|
Warfarin sodium
|
Incompatible
|
|---|
Amphotericin B cholesteryl sulfate complex
|
Idarubicin HCl
|
Pentamidine isethionate
|
Vinorelbine tartrate
|
Variable
|
|---|
Amiodarone HCl
|
Hetastarch in sodium chloride 0.9%
|
Hydromorphone HCl
|
Promethazine HCl
|
Vancomycin HCl
|
Actions and SpectrumActions
Based on spectrum of activity, classified as a first generation cephalosporin.a Has a limited spectrum of activity compared with second, third, and fourth generation cephalosporins.a
Usually bactericidal.a
Like other β-lactam antibiotics, antibacterial activity results from inhibition of bacterial cell wall synthesis.100 a
Spectrum of activity includes many gram-positive aerobic bacteria and some gram-negative aerobic bacteria; inactive against fungi and viruses.100 a
Gram-positive aerobes: active in vitro and in clinical infections against penicillinase-producing and nonpenicillinase-producing Staphylococcus aureus and S. epidermidis; Streptococcus pyogenes (group A β-hemolytic streptococci); S. agalactiae (group B streptococci); and S. pneumoniae.a 100 Enterococci and oxacillin-resistant (methicillin-resistant) staphylococci are resistant.100
Gram-negative aerobes: active in vitro and in clinical infections against some strains of Haemophilus influenzae, Escherichia coli, Klebsiella, Proteus mirabilis, and Enterobacter aerogenes.100 a Inactive against most other gram-negative bacteria, including Citrobacter, E. cloacae, Morganella, Providencia, Pseudomonas, and Serratia.100 a
Advice to Patients
Advise patients that antibacterials (including cefazolin) should only be used to treat bacterial infections; they do not treat viral infections (e.g., the common cold).100 115 116 117 119
Importance of completing full course of therapy, even if feeling better after a few days.100 115 116 117 119
Advise patients that skipping doses or not completing the full course of therapy may decrease effectiveness and increase the likelihood that bacteria will develop resistance and will not be treatable with cefazolin or other antibacterials in the future.100 115 116 117 119
