Antimicrobials
Posaconazole

Posaconazole

N/A
Moderate (40 to 70%)
See Additional Information

Spectrum of Activity

Dosing

General Information

  • LFTs

  • CBC

  • Electrolytes (specifically K+ and Mg++)

  • QTC

  • Serum trough monitoring

  • Elevated LFTs

  • Thrombophlebitis

  • Peripheral edema

  • Headache

  • Infusion reactions

  • Hypokalemia, hypomagnesemia

  • QTc prolongation

  • Nausea, vomiting, diarrhea

See Lexicomp; significant drug-drug interactions

Cost:

  • IV: $313.07/dose

  • Liquid: $12.44/mL

  • Tablet: $34.26/tablet

  • Absorption:
    • Oral suspension: Unpredictable and variable (optimal absorption with a high-fat meal in 4 divided doses; absorption may be sufficient if taken with a nutritional supplement or acidic beverage [eg, ginger ale])
    • Tablet (delayed-release): Predictable (preferably administered with food, but absorption is sufficient under fasting conditions)
  • Distribution: Vd: 
    • Oral: 287 L
    • Injection: ~261 L
  • Protein Binding: >98%; predominantly bound to albumin
  • Metabolism: 
    • Not significantly metabolized
    • 17% undergoes non-CYP-mediated metabolism, primarily via hepatic glucuronidation into metabolites
  • Bioavailability:
    • Oral: Suspension and delayed release tablets are not bioequivalent; higher plasma exposure observed with delayed release tablets
    • Suspension: Dependent upon gastric pH environment (decreased with higher pH or increased motility) and fed-conditions (increased in high-fat environment)
    • Delayed release tablets: Dependent upon fed condition: Fasted conditions: 54%; higher under high-fat fed conditions (51% increase in AUC)
  • Half-Life Elimination:
    • Suspension: 35 hours (range: 20 to 66 hours)
    • Tablets: 26 to 31 hours
    • Injection: ~27 hours
  • Time to Peak, Plasma:
    • Suspension: ~3 to 5 hours
    • Tablets: ~4 to 5 hours
  • Excretion: 
    • Feces 71% (~66% of the total dose as unchanged drug)
    • Urine 13% (<0.2% of the total dose as unchanged drug)