Antimicrobials
Clarithromycin

Clarithromycin

Medium
Moderate
See below under General Info

Dosing

General Information

Hospital Formulary Status Yes (PO solid, PO powder for susp)

In-Hospital Cost will be updated

PharmaCare Formulary Status Yes (PO solid, PO susp)

SA None

PharmaCare Coverage 250mg PO - $0.4452/tab 500mg PO - $0.8983/tab 500mg XL PO - $1.3578/tab 125mg/5ml PO susp recon - $0.2211/ml 250mg/5ml PO susp recon - $0.4318/ml

Outpatient Cost 250mg PO - $0.45-0.75/tab 500mg PO - $2.01-2.94/tab 500mg XL PO - $1.42-1.61/tab 125mg/5ml PO susp recon - $0.22-0.24/ml 250mg/5ml PO susp recon - $0.43-0.47/ml

  • CAP
  • Pertussis
  • URTI
  • H. pylori and mycobacterial infections

Monitor QTc in patients with increased risk

Gastritis (PO and IV)

  •  sx: nausea, vomiting, diarrhea, abdominal pain and cramping with subsequent loose stools
  •  abdominal cramping caused by stimulation of motilin receptors
  •  dysgeusia is common with clarithromycin but rare with azithromycin
  •  azithromycin and clarithromycin are better tolerated than erythromycin
  •  intolerance to one macrolide does not predict intolerance to another

QT interval prolongation and CV mortality (PO and IV)

  •  associated with increased CV and all-cause mortality over a 10-year period
  •  can occur in patients with CAD
  •  assess if patient is at risk for torsades de pointes (history of long QT interval, taking other QT-prolonging drugs, drug interactions, older age, electrolyte abnormalities)

Hearing loss (mainly with IV)

  •  can be reversible or irreversible
  •  especially at high doses

Other

  •  SJS
  •  drug reaction with eosinophilia and systemic symptoms (DRESS)
  •  pseudomembranous colitis
  •  exacerbations of myasthenia gravis

Recommend review of patient medications due to high frequency of significant interactions

  •  CYP450 interactions ++
  • Other QTc prolonging agents
  • Statins - increased rhabdo
  • CCBs - hypotension, AKI
  • Colchicine - increased bone marrow toxicity
  • Increased anticonvulsant levels
  • Increased tacrolimus levels

Antimicrobial class: Macrolide

Pregnancy category: C

Very high tissue penetration and concentration intracellularly means in vivo activity may not be predicted by in vitro testing.

Average serum half life: 5.0 hr

Urine penetration: Poor

Lung penetration: Therapeutic

CSF penetration: Poor

Biliary penetration: Therapeutic