Clarithromycin

General

• Type: macrolide
• Dosage Forms: 250, 500, 500ER; 125, 250/5ml
• Common Trade Names: Biaxin, Biaxin XL

Adult Dosing

• infections, bacterial
  • 250-500mg PO q12h x 7-14d
  • Alt: 1000mg ER PO qd x 7-14d

• chronic bronchitis, actue bacterial exacerbation
  • 1000mg ER PO q24 x 7d (with food, do not cut/crush/chew)
  • Alt: 250-500mg PO q12h x 7-14d

• pharyngitis/tonsillitis, streptococcal
  • 250mg PO q12h x 10d

• MAC primary prophylaxis
  • 500mg PO q12h

• MAC secondary prophylaxis, HIV
  • 500mg q12h (use with ethambutol)

• MAC treatment, disseminated
  • 500mg PO q12h (use with ethambutol)

• H. pylori infection
  • triple treatment: 500mg PO q12hr x 7-14d
  • dual treatment: 500mg PO q8h x 14d (give with Omeprazole 40mg qd x 14d)

• endocarditis prophylaxis, dental
  • 500mg PO x1 (30-60min before procedure)

Pediatric Dosing

• infections, bacteria
  • > 6 months: 15mg/kg/day PO divided q12h, max 1000mg/day

• otitis media, acute
  • 2mo-5yrs: 15mg/kg/day PO divided q12h x 10d
  • 6-12yrs: 15mg/kg/day PO divided q12 x 5-10d

• pharyngitis/tonsillitis, streptococcal
  • >6mo: 15mg/kg/day PO divided q12h x 7-10d

• MAC primary prophylaxis, HIV patients
  • 20mo-12yrs: 15mg/kg/day PO divided q12h; max 500mg/dose
  • >13yrs: 500mg PO q12h

• MAC secondary prophylaxis, HIV patients
  • 20mo-12yrs: 15mg/kg/day PO divided q12h; max 500mg/dose (use with ethambutol)
  • >13yrs: 500mg PO q12h (use with ethambutol)

• MAC treatments
  • 20mo-12yrs: 15-30mg/kg/day PO divided q12h; max 500mg/dose (use with ethambutol)
  • >13yrs: 500mg PO q12h (use with ethambutol)

• endocarditis prophylaxis, dental
  • 15mg/kg PO x1; max 500mg (30-60min before procedure)

• H. pylori infection
  • 20mg/kg/day PO divided BID x 7-14d; max 1000mg/day

Special Populations

• Pregnancy: C (risk cannot be ruled out)
• Lactation: safety unknown
• Renal Dosing
  • Adult
    • all uses with out ritonavir or atazanavir
      • GFR < 30: decrease dose 50% or give IR form q24h or ER form q48h
      • HD/PD: no supplement
    • concomitant ritonavir or atazanavir
      • GFR 30-60: decrease dose 50%
      • GFR < 30: decrease dose 75%
      • HD/PD: no supplement
  • Pediatric
    • all uses without ritonavir or atazanavir
      • GFR < 30: decrease dose 50% or give q24h
      • HD/PD: no supplement
    • concomitant ritonavir or atazanavir
      • not defined
• Hepatic Dosing
  • Adult: no adjustment
  • Pediatric: no adjustment

Contraindications

• Allergy to class/drug
• Liver disease
• Renal disease
• prolonged QT
• ventricular arrythmias or history of
• history of torsades de pointes
• uncorrected electrolyte abnormalities
• significant bradycardia
• caution if recent MI
• caution if CHF
• caution in female and elderly
• caution in myasthenia gravis

Adverse Reactions

Serious

• superinfection
• C-difficile-associated diarrhea
• hepatotoxicity
• interstitial nephritis
• pancreatitis
• QT prolongation
• ventricular arrhythmias
• torsades de pointes
• thrombocytopenia
• leukopenia
• neutropenia
• hearing loss, reversible
• seizures
• behavioral disturbances
• psychosis
• hallucinations
• psychiatric disturbance
• anaphylaxis
• erythema multiforme
• Stevens-Johnson Syndrome
• drug rash with eosinophilia and systemic sx
• myasthenia gravis exacerbation
• rhabdomyolysis

Common

• diarrhea
• nausea and vomiting
• taste changes
• abdominal pain
• dyspepsia
• headache
• rash

Pharmacology

• Half-life: 3-4 hours (increased with dosage increase)
• Metabolism: hepatic (rapid first-pass metabolism), CYP3A4
• Excretion: renal
• Mechanism of Action: interferes with bacterial protein synthesis by binding to a component of the 50S subunit

Antibiotic Sensitivities

Group	Organism	Sensitivity
Gram Positive	Strep. Group A, B, C, G	I
	Strep. Pneumoniae	I
	Viridans strep	X1
	Strep. anginosus gp	X1
	Enterococcus faecalis	R
	Enterococcus faecium	R
	MSSA	S
	MRSA	R
	CA-MRSA	I
	Staph. Epidermidis	R
	C. jeikeium	R
	L. monocytogenes	S
Gram Negatives	N. gonorrhoeae	I
	N. meningitidis	X1
	Moraxella catarrhalis	S
	H. influenzae	S
	E. coli	R
	Klebsiella sp	R
	E. coli/Klebsiella ESBL+	R
	E coli/Klebsiella KPC+	R
	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	R
	Yersinia enterocolitica	R
	Francisella tularensis	X1
	Brucella sp.	R
	Legionella sp.	S
	Pasteurella multocida	X1
	Haemophilus ducreyi	X1
	Vibrio vulnificus	X1
Misc	Chlamydophila sp	S
	Mycoplasm pneumoniae	S
	Rickettsia sp	X1
	Mycobacterium avium	S
Anaerobes	Actinomyces	S
	Bacteroides fragilis	R
	Prevotella melaninogenica	S
	Clostridium difficile	X1
	Clostridium (not difficile)	S
	Fusobacterium necrophorum	R
	Peptostreptococcus sp.	I

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

• Antibiotics (Main)

References

Authors

Ann Huang, Ross Donaldson, Michael O'Brien, MD, Daniel Ostermayer, Claire, Neil Young