Monitoring fluconazole blood concentrations

Fluconazole has high bioavailability, and plasma concentrations after oral and intravenous administration are generally predictable. Fluconazole plasma concentration monitoring is not routinely required; however, it may be considered in adults with:John 2019Muilwijk 2020Sandaradura 2021

• altered kidney function (eg adults with acute kidney injury, adults undergoing continuous renal replacement therapy, adults with augmented renal clearance)
• infection caused by a pathogen with a minimum inhibitory concentration (MIC) more than 4 mg/L (eg Nakaseomyces glabratus [previously named Candida glabrata])
• critical illness
• central nervous system infection
• therapeutic failure
• difficulties with medication compliance.

If fluconazole plasma monitoring is required, seek expert advice for information about appropriate targets.

For information on fluconazole plasma concentration monitoring in haematology patients, see the Australian and New Zealand antifungal consensus guidelines.