Low
Excellent
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Suspension
200 - 400 mg 2-3 times daily, based on indication and pathogen.
Consult guidelines.
Delayed Release
300 mg q12 h x 2 doses, then 300 mg daily.
For prophylaxis of invasive Aspergillus and Candida infections in severely immunocompromised patients
For Pediatric patients: restricted to use by Pediatric Infectious Diseases Service approval.
Treatment of invasive zygomycosis in combination with Amphotericin B
Monotherapy for zygomycosis after 7 days of combination therapy with Amphotericin B
Note: posaconazole requires up to 7 days to achieve steady state concentrations. ID consult is advised.
Prophylaxis of invasive fungal infection in immunocompromised patients such as stem cell transplant recipients
Treatment of invasive fungal infections such as candidiasis if conventional therapy has failed
Laboratory
Hepatic enzymes at baseline and every 1-2 weeks after
Therapeutic drug monitoring at steady state (5-7 days). Target >1.25 mcg/mL for invasive fungal disease or >0.7 mcg/mL for prophylaxis
Clinical
GI effects
Prolongation of QT interval with risk factors
Hypersensitivity
Photosensitivity
Drug-drug interactions
GI upset (~40%),
Headaches
Elevation in hepatic enzymes
Hypersensitivity
Rare but serious effects include QTc prolongation
Posaconazole is an inhibitor and is metabolized by cytochrome P4503A4; therefore, coadministration with other agents that are cytochrome P450 substrates, inducers, or inhibitors will result in significant drug interactions.
You must check for potential drug interactions when initiating Posaconazole therapy or starting a new medication in patients already receiving Posaconazole therapy.
Administration of the following agents with Posaconazole is contraindicated:
Terfenadine, Astemizole, Pimozide, Cisapride, Quinidine, Sirolimus, Halofantrine and ergot alkaloids
Posaconazole inhibits metabolism of the following agents. Dose reductions and close monitoring are recommended when Posaconazole is used with agents concomitantly:
Tacrolimus – reduce Tacrolimus dose to ⅓ and monitor levels
Cyclosporine – reduce Cyclosporine dose to ¾ and monitor drug level
Midazolam – consider dose reducing
Cimetidine, Rifabutin, Efavirenz and Phenytoin – unless the benefit outweighs the risk, AVOID concomitant use. If used together, monitor effect of the drugs and consider decreasing dose when Posaconazole is added
Statins (avoid Lovastatin and Simvastatin), vinca alkaloids, calcium channel blockers, Digoxin, Atazanavir, Ritanovir, QTc prolonging drugs (e.g. Amiodarone and Erythromycin) – monitor effect of the drugs and consider decreasing dose when Posaconazole is added
Cimetidine, Rifabutin, Phenytoin, Efavirenz, Esomeprazole, Metoclopramide may decrease Posaconazole blood levels.
High pharmacokinetic variability, dependent on fatty food administration (for solution).
The two oral formulations of posaconazole (delayed-release tablets and an oral suspension) are not interchangeable, and cannot be directly substituted without a change in dosage.
All orders for posaconazole must specify the dosage form, strength, and frequency
