• Type: First generation cephalosporin
  • Dosage Forms: capsule, oral suspension, tablet
  • Dosage Strengths: capsule: 500mg; oral suspension: 250mg/5mL, 500mg/5mL; tablet: 1g
  • Routes of Administration: PO
  • Common Trade Names: Duricef, Ultracef

Adult Dosing

Infections, bacterial

  • 1-2g/day PO divided q12-24h

Pharyngitis/tonsillitis, streptococcal

  • 1g PO divided q12-24h x 10days

Pediatric Dosing

Infections, bacterial

  • 30mg/kg/day PO divided q12-24h max 2g/day

Pharyngitis/tonsillitis, streptococcal

  • 30mg/kg/day PO divided q12-24h x 10days, max 1g/day

Special Populations

  • Pregnancy Rating: B (no evidence of harm)
  • Lactation: safe (no risk/minimal risk)
  • Renal Dosing
    • Adult
      • GFR 25-50: 1g x1, then 500mg q12h
      • GFR 10-25: 1g x1 then 500mg q24h
      • GFR < 10: 1g x1, then 500mg q36h
      • HD: give 0.5-1g supplement
      • PD: 500mg q24h
    • Pediatric
      • GFR 10-25: give q24h
      • GFR < 10: give q36h
      • HD: give supplement
      • PD: no supplement
  • Hepatic Dosing
    • Adult: not defined
    • Pediatric: not defined


  • Allergy to class/drug

Adverse Reactions


  • anaphylaxis
  • Stevens-Johnson syndrome
  • toxic epidermal necrolysis
  • angioedema
  • neutropenia
  • thrombocytopenia
  • pancytopenia
  • anemia, hemolytic
  • aplastic anemia
  • hemorrhage
  • seizures
  • superinfection
  • C.difficile-associated diarrhea


  • diarrhea
  • nausea
  • dyspepsia
  • urticaria
  • pruritus
  • rash
  • vomiting
  • ALT, AST elevation


  • Half-life:
    • 78-96 min, 20-25hr (ESRD)
  • Metabolism:
    • minimal, site unknown
  • Excretion:
    • urine primarily (>90% unchanged)
  • Mechanism of Action:
    • bacteriacidal; inhibits cell wall mucopeptide synthesis

Antibiotic Sensitivities[1]

Group Organism Sensitivity
Gram Positive Strep. Group A, B, C, G S
Strep. Pneumoniae S
Viridans strep S
Strep. anginosus gp X1
Enterococcus faecalis R
Enterococcus faecium X1
Staph. Epidermidis I
C. jeikeium R
L. monocytogenes R
Gram Negatives N. gonorrhoeae R
N. meningitidis R
Moraxella catarrhalis R
H. influenzae X1
E. coli S
Klebsiella sp S
E. coli/Klebsiella ESBL+ R
E coli/Klebsiella KPC+ R
Enterobacter sp, AmpC neg R
Enterobacter sp, AmpC pos R
Serratia sp R
Serratia marcescens X1
Salmonella sp R
Shigella sp R
Proteus mirabilis S
Proteus vulgaris R
Providencia sp. R
Morganella sp. R
Citrobacter freundii R
Citrobacter diversus R
Citrobacter sp. X1
Aeromonas sp X1
Acinetobacter sp. R
Pseudomonas aeruginosa R
Burkholderia cepacia R
Stenotrophomonas maltophilia R
Yersinia enterocolitica X1
Francisella tularensis X1
Brucella sp. X1
Legionella sp. R
Pasteurella multocida X1
Haemophilus ducreyi X1
Vibrio vulnificus X1
Misc Chlamydophila sp X1
Mycoplasm pneumoniae X1
Rickettsia sp X1
Mycobacterium avium X1
Anaerobes Actinomyces X1
Bacteroides fragilis X1
Prevotella melaninogenica X1
Clostridium difficile X1
Clostridium (not difficile) X1
Fusobacterium necrophorum X1
Peptostreptococcus sp. X1


  • S susceptible/sensitive (usually)
  • I intermediate (variably susceptible/resistant)
  • R resistant (or not effective clinically)
  • S+ synergistic with cell wall antibiotics
  • U sensitive for UTI only (non systemic infection)
  • X1 no data
  • X2 active in vitro, but not used clinically
  • X3 active in vitro, but not clinically effective for Group A strep pharyngitis or infections due to E. faecalis
  • X4 active in vitro, but not clinically effective for strep pneumonia

See Also


  1. Sanford Guide to Antimicrobial Therapy 2014