Antimicrobials
Posaconazole

Posaconazole

N/A
See Additional Information
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Spectrum of Activity

Dosing

General Information

  • Literature suggests trough of > 0.5 mg/L for prophylaxis and > 0.5-1.5 mg/L for treatment
  • Weekly CBC with differential, chemistries, renal and hepatic function
  • Liver transaminase elevations and rarely liver injury
  • Prolongation of QTc interval or other arrhythmias

For additional information (including full list of adverse effects) please see LexiComp

Product information suggests not coadminister posaconazole with the following drugs;

  • Sirolimus: can result in sirolimus toxicity (4.2, 7.1)
  • CYP3A4 substrates (pimozide, quinidine): can result in QTc interval prolongation and cases of Torsades de pointes
  • HMG-CoA Reductase Inhibitors primarily metabolized through CYP3A4: can lead to rhabdomyolysis
  • Ergot alkaloids: can result in ergotism

Please refer to Lexicomp for additional considerations and/or more information

200 mg/5 mL suspension (formulary item)

100 mg extended release tablet (formulary item) (do not crush)

  • Oral suspension and extended release tablets are not interchangable.
  • Oral suspension requires acidic pH and high fat meal for optimal absorption. Additionally, absorption is its rate limiting step requiring four times daily dosing if suspension is used for treatment.
  • Extended release tablet has improved absorption significantly. It is less effected by food for absorption and has generally higher absorption allowing for once daily dosing (after initial loading dose). Unfortunately is only been studied in adolescents and adults.
  • No data in neonates. Suspension contains polysorbate 80 and risk vs benefit would need to be considered.