• Type: Second generation cephalosporin
  • Dosage Forms: capsule, tablet, oral suspension
  • Dosage Strengths: capsule: 250mg, 500mg; tablet 500mg; oral suspension: 125mg/5mL, 250mg/5mL, 375mg/5mL
  • Routes of Administration: PO
  • Common Trade Names: Ceclor, Raniclor

Adult Dosing

Infection, bacterial

  • Immediate-release:
    • 250-500 mg PO q8h
      • Max: 2 g/day
  • Extended-release:
    • 500 mg ER PO q12h
      • Max 2 g/day

Pediatric Dosing

Infection, bacterial

  • 1+ mo
    • 20-40 mg/kg/day PO divided 18-12h
      • Max: 1 g/day

Special Populations

  • Renal Dosing
    • Adult:
      • No adjustment
      • HD: Give dose after dialysis
      • PD: No supplement
    • Pediatric
      • CrCl <10: Decrease dose 50%
      • HD: Give dose after dialysis
    • PD: No supplement
  • Hepatic Dosing
    • Adult:
      • Not defined
    • Pediatric
      • Not defined


  • Allergy to class/drug
  • Caution:
    • Hypersensitivity to penicillin
    • Renal impairment
    • Concurrent nephrotoxic agent
    • Seizure disorder
    • Recent abx-associated colitis history

Adverse Reactions




  • Half-life: 35-54 min; 2-3hr in ERSD
  • Metabolism: Partial, hepatic
  • Excretion: Urine primarily (60-85% unchanged)
  • Mechanism of Action: Inhibits cell wall mucopeptide synthesis; bactericidal

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 I
N. meningitidis I
Moraxella catarrhalis I
H. influenzae S
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 X1
Shigella sp X1
Proteus mirabilis S
Proteus vulgaris R
Providencia sp. R
Morganella sp. R
Citrobacter freundii R
Citrobacter diversus R
Citrobacter sp. I
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 R
Prevotella melaninogenica S
Clostridium difficile X1
Clostridium (not difficile) X1
Fusobacterium necrophorum X1
Peptostreptococcus sp. S


  • 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


  • Ahlfors CE. Benzyl alcohol, kernicterus, and unbound bilirubin. J Pediatr. 2001;139(2):317-319. [PubMed 11487763]
  • American Thoracic Society, “Guidelines for the Initial Management of Adults With Community-Acquired Pneumonia: Diagnosis, Assessment of Severity, and Initial Antimicrobial Therapy,” Am Rev Respir Dis, 1993, 148(5):1418-26. [PubMed 8239186]
  • Aronoff GR, Bennett WM, Berns JS, et al, Drug Prescribing in Renal Failure: Dosing Guidelines for Adults and Children, 5th ed. Philadelphia, PA: American College of Physicians; 2007, p 61, 153.
  • Boguniewicz M and Leung DYM, “Hypersensitivity Reactions to Antibiotics Commonly Used in Children,” Pediatr Infect Dis J, 1995, 14(3):221-31. [PubMed 7761188]
  • Campagna JD, Bond MC, Schabelman E, Hayes BD. The use of cephalosporins in penicillin-allergic patients: a literature review. J Emerg Med. 2012; 42(5):612-620. [PubMed 21742459]
  • Cefaclor Capsules [prescribing information]. Eatontown, NJ: West-Ward Pharmaceuticals; July 2015.
  • Cefaclor Extended-Release Tablets [prescribing information]. North Wales, PA: Teva Pharmaceuticals; December 2014.
  1. Sanford Guide to Antimicrobial Therapy 2014