Cefazolin

Cefazolin is a first-generation cephalosporin antibiotic used to treat various bacterial infections. It is effective against Gram-positive bacterial infections by Staphylococcus aureus and Streptococcus species. It is available as an intravenous (IV) or intramuscular (IM) injection. Cefazolin is a potent antibacterial agent in a clinical setting.

Drug Class

Cefazolin belongs to the beta-lactam antibiotics and their subclass 1st-generation cephalosporins. These antibiotics are more effective against Gram-positive bacteria than Gram-negative organisms.

Chemical Structure

It consists of a beta-lactam ring and a dihydrothiazine ring.

• Chemical Formula: C14H13N8O5S3

• Molecular Weight: 456.5 g/mol

Mechanism of Action

Cefazolin is a bactericidal medication. It kills bacteria by destroying their cell walls. Cefazolin binds to penicillin-binding proteins (PBPs) and inhibits their activity. It results in cell wall weakening and bacterial death.

Uses of Cefazolin

Cefazolin is used for the following types of infections.

• Skin and Soft Tissue Infections: Includes abscesses, cellulitis, and wound infections.
• Respiratory Tract Infections: Such as pneumonia, bronchitis, and tonsillitis.
• Urinary Tract Infections (UTIs), particularly those caused by E. coli and Klebsiella species.
• Bone and Joint Infections, including osteomyelitis and septic arthritis.
• Surgical Prophylaxis: Prevents infection during surgeries, particularly in orthopaedic and cardiac procedures.

Dosage and Formulations

Dosage Recommendations

The dosage of cefazolin depends on factors like infection type, severity, and the patient’s kidney function. It is usually administered IV or IM, with adult and pediatric doses varying.

• Adults
  • Mild to Moderate Infections: 250 mg to 500 mg every 8 hours.
  • Severe Infections: 1 to 2 grams every 8 hours.
  • Surgical Prophylaxis: 1 to 2 grams before surgery, followed by additional doses if surgery lasts longer than 2 hours.
• Children
• • • Mild to Moderate Infections: 25 to 50 mg/kg/day, divided into 3-4 doses.
    • Severe Infections: 50 mg/kg/day, divided into 3-4 doses.

Formulations

• Injectable Solution: Cefazolin is available as a powder to be reconstituted for intravenous (IV) or intramuscular (IM) injection. The typical vial strengths are 500 mg, 1 g, and 2 g.

Side Effects of Cefazolin

It can cause side effects in some individuals.

Common Side Effects

• Nausea,
• vomiting,
• Diarrhea.
• Pain
•  redness,
• Swelling at the site of injection
• Rashes and Itching

Serious Side Effects

• Anaphylaxis – Severe allergic reactions
• Renal Toxicity
• Blood Dyscrasias – Thrombocytopenia (low platelet count), leukopenia (low white blood cell count), and eosinophilia (high eosinophil count
• Severe Diarrhea

Drug Interactions of Cefazolin

• Probenecid increases the concentration of cefazolin in the body by inhibiting its renal excretion.
• When administered with Aminoglycosides, it can increase the risk of nephrotoxicity.
• When combined with Anticoagulants such as Warfarin, it can increase the risk of bleeding due to cefazolin’s effect on platelets.
• Use with caution Other Antibiotics

Contraindications

Cefazolin should not be used in the following conditions.

• Allergic Reactions to Cephalosporins or Penicillins.
• Severe Renal Impairment
• Neonates and Infants

Popular Brand Names for Cefazolin

Brand Name	Manufacturer	Strength	Route of Administration	Indications
Ancef	GlaxoSmithKline	500 mg, 1 g	IV/IM	Skin infections, pneumonia, UTIs
Kefzol	Eli Lilly	500 mg, 1 g	IV/IM	Respiratory infections, osteomyelitis
Zolicef	Aurobindo Pharma	1 g, 2 g	IV/IM	Surgical prophylaxis, soft tissue infections
Cefazolin Sandoz	Sandoz	1 g, 2 g	IV/IM	Bone infections, surgical prophylaxis

Special Instructions for Users

Users should follow important instructions while using Cefazolin to ensure safe and effective use.

• Monitor renal function.
• Provide your Allergy history Information to your doctor.
• Use Proper Injection Technique to prevent infection at the injection site.
• Complete the entire prescribed course to prevent bacterial resistance.
• Avoid alcohol consumption while taking cefazolin

Pregnancy and Lactation

• Pregnancy Category B – should be used only if needed during pregnancy.
• Breastfeeding – It is excreted in breast milk and should be used with caution during breastfeeding.

Conclusion

Cefazolin is a broad-spectrum antibiotic medication that has activity against Gram-positive bacteria. It is the drug of choice for skin, respiratory, and urinary tract infections. Adhere to dosage guidelines given by your health professional and complete the full course of treatment for optimal outcomes.