Cefazolin

Class: First-generation cephalosporin antibiotic

Mechanism of Action: Inhibits bacterial cell wall synthesis by binding to penicillin-binding proteins, leading to bacterial lysis. Effective mainly against Gram-positive bacteria and some Gram-negative organisms.

Indications

• Skin and soft tissue infections
• Bone and joint infections
• Urinary tract infections
• Respiratory tract infections
• Endocarditis (susceptible organisms)
• Perioperative prophylaxis in surgery

Dosage

• Adults: 1–2 g IV every 8 hours (adjust based on severity and renal function)
• Children: 25–50 mg/kg IV every 8 hours

Maximum Dose

6 g/day in adults

Major Side Effects

• Allergic reactions: rash, urticaria, anaphylaxis
• Gastrointestinal disturbances: nausea, vomiting, diarrhea
• Local reactions at injection site
• Hematologic effects: eosinophilia, thrombocytopenia (rare)

Contraindications

• Hypersensitivity to cephalosporins or penicillin
• History of severe allergic reaction (anaphylaxis) to beta-lactams

Compatible Fluids

• 0.9% Sodium Chloride
• 5% Dextrose
• Ringer’s Lactate (check compatibility)

Route of Administration

• Intravenous (IV)
• Intramuscular (IM)

Type of Administration

• IV: slow injection or infusion
• IM: deep injection into a large muscle

Special Precautions

• Adjust dose in renal impairment
• Monitor for allergic reactions, especially first dose
• Prolonged use may lead to superinfection or Clostridioides difficile colitis
• Use cautiously in patients with history of seizures