osudhkosh

Generic

Cefazolin

4 brands available in the market

At a glance

Cefazolin is a first-generation cephalosporin antibiotic used in the treatment of serious bacterial infections of the respiratory tract, urinary tract, skin, biliary tract, bones and joints, genital tract, bloodstream, and heart, as well as for perioperative prophylaxis. It kills bacteria by inhibiting bacterial cell wall synthesis.

Description

Cefazolin is a first-generation broad-spectrum parenteral cephalosporin antibiotic. It interferes with bacterial cell wall synthesis by inhibiting transpeptidase enzyme, resulting in weakening of the bacterial cell wall, swelling, and rupture.

Cefazolin is indicated for respiratory tract infections, urinary tract infections, skin and skin structure infections, biliary tract infections, bone and joint infections, genital infections, septicemia, endocarditis, and perioperative prophylaxis.

Indications
  • Respiratory tract infections
  • Urinary tract infections
  • Skin and skin structure infections
  • Biliary tract infections
  • Bone and joint infections
  • Genital infections
  • Septicemia
  • Endocarditis
  • Perioperative prophylaxis
Therapeutic class

First generation cephalosporins

Pharmacological class

Cephalosporin Antibiotic

Pharmacology

Cefazolin is a first-generation broad-spectrum parenteral cephalosporin antibiotic that interferes with bacterial cell wall synthesis by inhibiting transpeptidase enzyme. As a result, the bacterial cell wall is weakened, the cell swells, and then ruptures.

Mechanism of action

Cefazolin binds to penicillin-binding proteins (PBPs), inhibiting the final transpeptidation step of peptidoglycan synthesis in the bacterial cell wall, preventing cell wall assembly and causing bacterial cell death.

Dosage

Adults:
• Mild infections (Gram-positive cocci): 250-500 mg every 8 hours
• Moderate-severe infections: 500 mg-1 g every 6-8 hours
• Severe, life-threatening infections (endocarditis, septicemia): 1-1.5 g every 6 hours (up to 12 g/day in rare instances)
• Acute uncomplicated UTI: 1 g every 12 hours
• Pneumococcal pneumonia: 500 mg every 12 hours

Perioperative Prophylaxis:
• 1 g IM or IV 30-60 minutes before surgery
• For lengthy procedures (≥2 hours): 500 mg-1 g IM or IV during surgery
• Postoperative: 500 mg-1 g IM or IV every 6-8 hours for 24 hours
• Open-heart surgery and prosthetic arthroplasty: may continue for 3-5 days

Children:
• Mild-moderate infections: 25-50 mg/kg/day (in 3-4 divided doses)
• Severe infections: up to 100 mg/kg/day
• Safety in premature infants and neonates not established

Renal impairment (CrCl):
• 35-54 mL/min: Full unit dose every 8 hours
• 11-34 mL/min: Half unit dose every 12 hours
• <10 mL/min: Half unit dose every 18-24 hours

Hepatic impairment: No dose adjustment needed.

Administration: Deep IM injection, slow IV injection (3-5 minutes), or intermittent/continuous IV infusion.

Administration

Administered by healthcare professionals as deep IM injection, slow IV injection (3-5 minutes), or intermittent/continuous IV infusion. After reconstitution, the solution is stable for 24 hours at room temperature and 10 days under refrigeration (5°C).

Missed dose

Hospital-only medicine. Administered by doctor or nurse. If you miss a dose, consult your doctor.

Side effects

Common side effects: Injection site reactions (pain, swelling, rash, hard lump), diarrhea, abdominal pain/cramps, nausea, vomiting, loss of appetite, skin rash/itching, urticaria, white patches/sores in mouth/lips, vaginal itching/discharge, heartburn, gas, rectal itching, confusion, weakness, hypotension, drowsiness, headache, allergic reactions.

Seizures may occur with inappropriately high doses or in patients with renal impairment.

Precautions & warnings
  • Cefazolin is for parenteral use only.
  • Caution in patients with history of allergy to cephalosporins or penicillins (cross-allergy).
  • Caution in patients with history of gastrointestinal disease, particularly colitis.
  • If rash, itching, swelling of face/mouth, or difficulty breathing occurs, discontinue and inform your doctor.
  • Severe and persistent diarrhea may indicate pseudomembranous colitis.
  • Avoid alcohol consumption (may increase side effects).
  • Adjust dose based on renal function.
Contraindications
  • Known allergy to cephalosporin group of antibiotics
Drug interactions
  • Probenecid: Decreases renal tubular secretion of cefazolin, resulting in increased and prolonged blood levels.
  • Vitamin K antagonists (warfarin): May enhance anticoagulant effect.
  • BCG, typhoid vaccine, sodium picosulfate: May diminish therapeutic effect.
  • Fosphenytoin and phenytoin: May decrease protein binding.
  • Aminoglycosides: May increase nephrotoxic effects.
Food interactions

Alcohol consumption does not cause harmful side effects (general caution advised).

Use in pregnancy

Generally considered safe during pregnancy (Category B). Animal studies have shown low or no adverse effects; limited human studies available. Use during pregnancy only if clearly needed.

Pregnancy Category: B — always consult a doctor before taking during pregnancy.

Use in lactation

Safe during breastfeeding (if prescribed). Cefazolin is excreted in breast milk in very low concentrations and is not harmful to the baby. Avoid prolonged use (risk of rash and diarrhea).

Pediatric use

Safety in premature infants and neonates has not been established. Children: 25-50 mg/kg/day (3-4 divided doses); severe infections: up to 100 mg/kg/day.

Geriatric use

No specific dose adjustment required for elderly; adjust dose based on renal function.

Renal / hepatic impairment
Renal impairment: Dose adjustment required based on creatinine clearance (see dosage section).

Hepatic impairment: No dose adjustment needed.
Overdose effects

Overdose symptoms: Nausea, vomiting, diarrhea, seizures (especially with renal impairment). Treatment: Supportive and symptomatic; hemodialysis may be effective.

Storage conditions

Reconstituted solution is stable for 24 hours at room temperature and 10 days under refrigeration (5°C). Store below 30°C. Keep out of reach of children.

Chemical structure

Cefazolin (First Generation Cephalosporin)

Common questions

What is Cefazolin used for?
It is used for serious bacterial infections (respiratory, urinary tract, skin, biliary, bone, joint, bloodstream, heart) and surgical infection prophylaxis.
How is it administered?
It is administered as a deep IM injection, slow IV injection, or IV infusion by a healthcare professional.
What are the side effects?
Injection site pain/swelling, diarrhea, nausea, rash, abdominal pain may occur.
Who should not use this medicine?
Patients with allergy to cephalosporins should not use it.
Can it be used during pregnancy?
Generally considered safe during pregnancy (Category B), but consult your doctor.
⚠️ This information is for educational purposes only — not a substitute for medical advice. Consult a registered physician before taking any medicine.