Adult Dosing

  • IV: 3-4 g/dose q4-6hr; not to exceed 24 g/24hr
  • IM: 2-3 g/dose q6-12hr; not to exceed 24 g/24 hr

Pediatric Dosing

  • Neonates: 100 mg/kg IV/IM q12h
  • Infants and Children: 200-300 mg/kg/day IV/IM divided q4-6hr

Special Populations

  • Pregnancy Rating: B
  • Lactation:
  • Renal Dosing
    • Adult:
    • CrCl 20-40 mL/min: 3-4 g q8hr
    • CrCl <20 mL/min: 3-4 g q12hr
    • Pediatric
  • Hepatic Dosing
    • Adult
    • Pediatric


  • Allergy to class/drug
  • Caution
    • Non-anaphylactic hypersensitivity to beta-lactams
    • Asthma, cystic fibrosis
    • Recent antibiotic-associated colitis
    • Seizure disorder
    • Renal impairement
    • Sodium restriction
    • Hypokalemia
    • Bleeding risk

Adverse Reactions




  • Half-life: 30-80min
  • Metabolism: Hepatic
  • Excretion: urinary
  • Mechanism of Action: Inhibits biosynthesis of cell wall mucopeptides and stage of active multiplication; has antipseudomonal activity

Antibiotic Sensitivities[1]

Group Organism Sensitivity
Gram Positive Strep. Group A, B, C, G S
Strep. Pneumoniae S
Viridans strep I
Strep. anginosus gp S
Enterococcus faecalis S
Enterococcus faecium I
Staph. Epidermidis R
C. jeikeium R
L. monocytogenes S
Gram Negatives N. gonorrhoeae X2
N. meningitidis S
Moraxella catarrhalis I
H. influenzae I
E. coli S
Klebsiella sp S
E. coli/Klebsiella ESBL+ R
E coli/Klebsiella KPC+ R
Enterobacter sp, AmpC neg S
Enterobacter sp, AmpC pos S
Serratia sp S
Serratia marcescens X1
Salmonella sp S
Shigella sp S
Proteus mirabilis S
Proteus vulgaris S
Providencia sp. S
Morganella sp. S
Citrobacter freundii S
Citrobacter diversus S
Citrobacter sp. S
Aeromonas sp S
Acinetobacter sp. R
Pseudomonas aeruginosa S
Burkholderia cepacia X1
Stenotrophomonas maltophilia I
Yersinia enterocolitica S
Francisella tularensis X1
Brucella sp. X1
Legionella sp. R
Pasteurella multocida S
Haemophilus ducreyi X1
Vibrio vulnificus X1
Misc Chlamydophila sp R
Mycoplasm pneumoniae R
Rickettsia sp X1
Mycobacterium avium X1
Anaerobes Actinomyces S
Bacteroides fragilis R
Prevotella melaninogenica S
Clostridium difficile X2
Clostridium (not difficile) S
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


  1. Sanford Guide to Antimicrobial Therapy 2014