First-Generation Cephalosporin
Gram-positive bacteria: Methicillin-susceptible Staphylococcus aureus (MSSA), coagulase –negative Staphylococci, penicillin-susceptible Streptococcus pneumoniae, Streptococci spp.
Gram-negative bacteria: Moraxella catarrhalis, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis
Cephalosporins exert bactericidal activity by interfering with the later stages of bacterial cell wall synthesis through inactivation of one or more penicillin-binding proteins and inhibiting cross-linking of the peptidoglycan structure. The cephalosporins are also thought to play a role in the activation of bacterical cell autolysins which may contribute to bacterial cell lysis.
Cephalosporins produce time-dependent killing.
500mg dose; Cmax: 16.2 mcg/ml; Half-life: 1.9 mcg/ml; Protein binding: 18-20%; Table 10
Hematologic: Neutropenia, leukopenia, eosinophilia, thrombocytopenia, thrombocytosis, impaired platelet aggregation
Dermatologic: Rash (maculopapular), puritis, urticaria
Gastrointestinal: Diarrhea
Hepatic: Abnormal liver function tests
Renal: Interstitial nephitis
Other: Anaphylaxis
PO: 500mg capsule, 1gram tablet
125mg/5ml, 250mg/5ml, 500mg/5ml powder for reconstitution (suspension)
Adult doses: 0.5-1gram PO q12-24h
Pharyngitis/tonsillitis: 1gram PO q24h or divided q12h x 10 days
Skin/skin structure infection: 1gram PO q24h or divided q12h
Urinary tract infection (uncomplicated): 1-2grams PO q24h or divided q12h
Urinary tract infection (complicated): 1gram PO q12h
Pediatric doses: 30mg/kg/day divided q12-24h
Impetigo: 30 mg/kg PO q24h or divided q12h, maximum 2grams per day
Pharyngitis/tonsillitis: 30 mg/kg PO q24h or divided q12h x 10 days, maximum 2grams per day
Skin/skin structure infection: 30 mg/kg/day PO divided q12h, maximum 2grams per day
Urinary tract infection: 30 mg/kg/day PO divided q12h, maximum 2grams per day
Disease state based dosing:
Renal failure: CrCl greater than 50 mL/min, usual dose and interval
CrCl 25-50 mL/min, 500 mg every 12 hr
CrCl 10-25 mL/min, 500 mg every 24 hr
CrCl less than 10 mL/min, 500 mg every 36 hr
Hepatic failure: No dosing changes recommended at this time.
Contraindications: Hypersensitivity to cephalosporins
Precautions: hypersensitivity to penicillins
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, signs and symptoms of infection (e.g. fever, WBC)
Toxic: Urinalysis, BUN, SCr, AST and ALT, neutropenia and leukopenia