Haemophilus influenzae, Moraxella catarrhalis, Neisseria meningitides, Neisseria gonorrhoeae, E. Coli, P. aeruginosa
Mechanism of Action:
Cephalosporins exert bactericidal activity by interfering with bacterial cell wall synthesis and inhibiting cross-linking of the peptidoglycan. The cephalosporins are also thought to play a role in the activation of bacterical cell autolysins which may contribute to bacterial cell lysis.
Cephalosporins exhibit time-dependent killing (T > MIC)
Dose of 1g: Cmax: 83 mcg/L; Half-life: 1.8 hours; Volume of distribution: 13.6L; Table 11
Hypersensitivity: Maculopapular rash, Urticaria, Pruritis, Anaphylaxis/angioedema, eosinophilia
Hematologic: Hypoprothrombinemia, Neutropenia, Leukopenia, Thrombocytopenia
GI: Diarrhea, C. difficile disease
Renal: Interstitial nephritis
IV: 1g, 2g, 6g, 10g, 500mg
Dosing in adults:
Bone and/or joint infection: 2 g IV q12h
Intra-abdominal infection: 2 g IV q8h
Meningitis: 2g IV q8h
Pneumonia: 0.5-1g IV q8h
Uncomplicated UTI: 250mg IV/IM q12h
Complicated UTI: 500mg IV/IM q8-12h
Dosing in pediatrics:
75-150mg/kg/day divided q8h
Disease state based dosing:
Renal failure: CrCl > 50mL/min: standard dosing
CrCl 30-50mL/min: 1g q12h
CrCl 10-29mL/min: 1g q24h
CrCl < 10mL/min: 1g q48h
Hepatic failure: No dosing changes recommended at this time.
Dosing during Continuous Renal Replacement Therapy
CVVH (Continuous venovenous hemofiltration): 1-2g IV q12h
CVVHD (Continuous venovenous hemodialysis): 2g IV q12h
CVVHDF (Continuous venovenous hemodiafiltration) 2g IV q12h
Note: CVVH is mainly for fluid removal alone. Many institutions will employ more CVVHD or CVVHDF which combine dialysis with fluid removal.
Precautions: hypersensitivity to penicillins, history of gastrointestinal disease, particularly colitis, renal impairment, risk factors for altered prothrombin time (renal or hepatic impairment, poor nutritional status, prolonged course of antibiotic therapy)
Chloramphenicol: decreased ceftazidime effectiveness
Live Typhoid Vaccine: decreased immunological response to the typhoid vaccine
Category B: No evidence of risk in humans but studies inadequate.
Therapeutic: Culture and sensitivities, serum levels, signs and symptoms of infection, white blood cell count
Toxic: Urinalysis, BUN, SCr, AST and ALT, skin rash, Neutropenia and leukopenia, Prothrombin time in patients with renal or hepatic impairment or poor nutritional state, as well as patients receiving a protracted course of antimicrobial therapy, and patients previously stabilized on anticoagulant therapy.
Brand names/Manufacturer: CeptazÒ/Glaxo Smith Kline; FortazÒ/Glaxo Smith Kline; TazicefÒ/Bristol-Myers Squibb; TazidimeÒ/Eli Lilly;