[Posaconazole photo]
KEY POINTS
- Posaconazole (Noxafil) is a triazole antifungal that works by inhibiting the synthesis of ergosterol
- Ergosterol is the primary sterol in the fungal cell wall
- Has activity against fungi such as Candida species, Aspergillus species, and zygomycetes
- FDA-approved for:
- Prophylaxis versus invasive aspergillosis in severely immunocompromised patients
- Oropharyngeal candidiasis
- Prophylaxis versus invasive candidiasis in severely immunocompromised patients
- Available oral and injectable
- The delayed-release tablets and oral suspensions are not interchangeable directly, dosage must be adjusted
- Dose and frequency vary depending on the indication
- Usually dosed in either 200mg, 300mg, or 400mg per dose
- The IV formulation is generally avoided for creatinine clearance below 50 mL/min, because the vehicle the drug is provided in can accumulate and cause toxicity
- Drug levels are frequently monitored to ensure adequate absorption
- The delayed-release tablet should be taken with food
- The oral suspension should be given within 20 minutes of a full meal
- Beware drug-drug interactions, posaconazole use is contraindicated with many other drugs
- Some adverse reactions to beware include: hypokalemia, diarrhea, nausea, headache, fever, prolonged QT interval, and liver toxicity
RESOURCES
- Posaconazole Package Insert (oral solution)
- Posaconazole Package Insert (delayed-release tablet)
- Posaconazole Package Insert (intravenous)
- 2016 IDSA Aspergillus Guideline
- 2016 IDSA Candidiasis Guideline
- 2014 Therapeutic Drug Monitoring of Antifungal Agents – Guidelines from the British Society for Medical Microbiology
- 2016 Review of Therapeutic Drug Monitoring of Posaconazole
- 2006 Pharmacology of Systemic Antifungal Agents