Pharmacy Services

Posaconazole (Noxafil®) Dosing Errors Due to Different Oral Formulations

12 January 2016

Posaconazole is an antifungal agent that is available in two oral formulations, a suspension and a delayed-release tablet. The oral formulations are not bioequivalent and dosing regimens are not interchangeable. Switching formulations without adjusting the dose may lead to supra- or subtherapeutic drug concentrations. Eleven events have been reported to FDA describing patients who switched posaconazole formulations without changing to the correct dose. One patient died and another required hospitalization.

FDA revised posaconazole labeling, prescribing information, and patient information to alert healthcare providers and patients that the two dosage forms cannot be directed substituted and require a change in dose and frequency. Include the dosage form, strength, and dosing frequency on all posaconazole prescriptions to minimize the risk of medication errors. Educate patients to expect a dosage change if switching oral formulations.

Additional information:

January 12, 2016; University of Utah, Drug Information Service. Copyright 2016, Drug Information Service, University of Utah, Salt Lake City, UT.