Antibiotic, Bactericidal, Cephalosporin antibiotic, First generation cephalosporin

Brand Names

Ancef®, CeFAZolin sodium®, Kefzol®, Zolicef®

Drug Information


First generation cephalosporin in injectable form, bactericidal against susceptible bacteria, particularly gram positive bacteria.

Achieves the greatest serum concentration and has the longest half life of all the cephalosporins


  • Contraindicated in patients with history of hypersensitivity to cephalosporin antibiotics and possibly to penicillin related antibiotics because of the potential for cross reactivity.
  • Use only when benefit outweighs the risk during pregnancy as safety has not been established.
  • Use caution in patients with pre existing kidney disease, particularly in higher than recommended doses or with prolonged treatment.
  • Extra label use of cephalosporin antibiotics in food animals is prohibited by the FDA.

Adverse Effects

  • Can cause pain at the injection site, although it is less likely with CeFAZolin as compared to other cephalosporins.
  • Sterile abscesses or other local tissue reactions such as thrombophlebitis from IV injection can occur.
  • Hypersensitivity reactions which includes anaphylaxis, blood changes, rash and fever can occur.
  • GI effects are less likely but can occur-anorexia, diarrhea or vomiting especially after fast IV injection.
  • Renal impairment can occur although less likely in patients with normal kidney function.
  • High dose or prolonged treatment can cause neurotoxicity, neutropenia, agranulocytosis, thrombocytopenia, hepatitis, positive Coombs test, interstitial nephritis and tubular necrosis.


General Interactions
  • Probenecid blocks tubular secretion resulting in higher serum levels and longer half life of CeFAZolin.

Category Interactions
  • Bactericidal antibiotics perform best on actively growing bacteria and therefore bacteriostatic drugs should not be used concurrently.
Nephrotoxic drug
  • Use caution with other renal toxic drugs.


Give IV injection slowly as vomiting may occur with rapid injection.
After reconstitution, solution is stable for 24 hours at room temperature or 96 hours if refrigerated.
If immediately frozen after reconstitution it is stable for 12 weeks in the freezer.
For information regarding compatibility in solution or combination with other drugs, refer to specialized reference material.

Available Forms

  • Powder for injection- 250, 500 mg, 1, 5, 10 and 20g.; Ancef® , Kefzol®, Zolicef®, CeFAZolin Sodium® For IV infusion 500 mg in 5% dextrose in water, 1 gram in 5% dextrose in water and 1 gram in 10 mL vials; Ancef®, Kefzol®
Veterinary – General
  • None