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; MAX, 600mg/day; then 10mg/kg/day (in combination with isoniazid) for 4 months or longer as needed
• Inactive TB, HIV+: 600mg PO daily for 4 months
• Meningitis: 600mg IV once daily (with vanc/cephalosporin)
• Bartonellosis: 300mg PO or IV q12h plus doxycycline
• 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

Special Populations

• Pregnancy Rating: C
• Lactation: Infant risk minimal
• Renal Dosing:
  • Adult
  • Pediatric
• Hepatic Dosing
  • Adult
  • Pediatric

Contraindications

• Allergy to class/drug
• concomitant use with atazanavir, darunavir, fosamprenavir, saquinavir, tipranavir, rilpivirine or elvitegravir/cobicistat

Adverse Reactions

Serious

• Agranulocytosis
• DIC
• Hepatotoxicity
• Nephrotoxicity

Common

• nausea/vomiting/diarrhea
• headache, dizziness, fatigue, disequilibrium, weakness
• pruritus, flushing
• turns your excretions orange!

Pharmacology

• Half-life: 3-5hr
• Metabolism: hepatic
• Excretion:
• Mechanism of Action: inhibits bacterial RNA synthesis

Antibiotic Sensitivities

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

Source

Authors

Ross Donaldson, Claire, Kaoru Itakura, Neil Young, Daniel Ostermayer