Rifampin

General

  • Type: bactericidal antibiotic
  • Dosage Forms: 150, 300; PO, IV
  • Common Trade Names: Rifadin

Adult Dosing

Active TB

  • 10mg/kg/day (in combination with isoniazid and pyrazinamide) PO or IV for 2 months
    • Then 10mg/kg/day (in combination with isoniazid) for 4 months or longer as needed
    • MAX, 600mg/day

Inactive TB, HIV+

  • 600mg PO daily for 4 months

Meningitis

Bartonellosis

Brucellosis

  • 15-20mg/kg/day PO/IV in 1 or 2 divided doses for at least 6 weeks in combination with a tetracycline
    • MAX 600 to 900mg/day

Infective endocarditis

  • 300mg IV or PO every 8 hours for a minimum of 6 weeks, in combination with appropriate antimicrobial therapy

Hansen Disease

Anthrax, systemic

  • 600 mg IV q12h for at least 2 wk as part of a multi-drug regimen
    • Switch to PO abx x60 days total if inhalational exposure

Pediatric Dosing

Active TB

  • <15 yo
    • 10-20 mg/kg PO/IV qd for at least 6mo
      • Max: 600 mg/day
  • 15+ yo
    • 10 mg/kg PO/IV qd for at least 6mo
      • Max: 600 mg/day

Latent TB

  • <15 yo
    • 10-20 mg/kg PO/IV qd x4mo
      • Max: 600 mg/day
  • 15+ yo
    • 10 mg/kg PO/IV qd x4mo
      • Max: 600 mg/day

H. influenza prophylaxis

  • <1 mo
    • 10mg/kg PO/IV q24h x4 days
      • Max: 600 mg/day
  • 1+ mo
    • 20 mg/kg PO/IV q24h x4 days
    • Max: 600 mg/day

Meningcococcal prophylaxis

  • <1 mo
    • 5mg/kg PO/IV q24h x4 days
      • Max: 600 mg/day
  • 1+ mo
    • 10 mg/kg PO/IV q24h x4 days
    • Max: 600 mg/day

Endocarditis, Staphylococcal prosthetic valve

Hansen Disease

  • Paucibacillary, 10-14 yo
  • Paucibacillary, 15+ yo
  • Multibacillary, 10-14 yo
  • Multibacillary, 15+ yo

Anthrax, systemic

  • Neonates >32 wk gestation
    • 10-20 mg/kg/day IV divided q12-24h for at least 2 wk as part of multi-drug regimen
  • 1+ mo
    • 20 mg/kg/day IV divided q12h for at least 2 wk as part of multi-drug regimen
      • Max: 300 mg/dose

Special Populations

  • Pregnancy Rating: C
  • Lactation: Infant risk minimal
  • Renal Dosing:
    • Adult
      • CrCl <50: Consider decreasing dose 0-50%
      • HD/PD: No supplment
    • Pediatric
      • CrCl <50: Consider decreasing dose 0-50%
      • HD/PD: No supplment
  • Hepatic Dosing
    • Adult
      • Avoid Use
    • Pediatric
      • Avoid Use

Contraindications

  • Allergy to class/drug
  • IM or SC administration
  • Concomitant use with atazanavir, darunavir, fosamprenavir, saquinavir, tipranavir, rilpivirine or elvitegravir/cobicistat

Adverse Reactions

Serious

Common

Pharmacology

  • Half-life: 3-5hr, 2-3hr with repeat dosing
  • Metabolism: Hepatic
  • Excretion: Bile; Urine <30%
  • Mechanism of Action: inhibits bacterial RNA synthesis

Antibiotic Sensitivities[1]

Group Organism Sensitivity
Gram Positive Strep. Group A, B, C, G S
Strep. Pneumoniae S
Viridans strep X1
Strep. anginosus gp X1
Enterococcus faecalis I
Enterococcus faecium R
MSSA S
MRSA S
CA-MRSA S
Staph. Epidermidis S
C. jeikeium S
L. monocytogenes S
Gram Negatives N. gonorrhoeae X2
N. meningitidis S
Moraxella catarrhalis S
H. influenzae S
E. coli R
Klebsiella sp R
E. coli/Klebsiella ESBL+ R
E coli/Klebsiella KPC+ I
Enterobacter sp, AmpC neg R
Enterobacter sp, AmpC pos R
Serratia sp X1
Serratia marcescens R
Salmonella sp R
Shigella sp R
Proteus mirabilis X1
Proteus vulgaris R
Providencia sp. X1
Morganella sp. X1
Citrobacter freundii X1
Citrobacter diversus X1
Citrobacter sp. X1
Aeromonas sp X1
Acinetobacter sp. R
Pseudomonas aeruginosa R
Burkholderia cepacia R
Stenotrophomonas maltophilia X1
Yersinia enterocolitica X1
Francisella tularensis S
Brucella sp. S+'
Legionella sp. X1
Pasteurella multocida X1
Haemophilus ducreyi X1
Vibrio vulnificus X1
Misc Chlamydophila sp X2
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

Key

  • 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

References

  1. Sanford Guide to Antimicrobial Therapy 2014