Dosing Antifungals in Obesity: a Literature Review
Purpose of Review
To summarize the available evidence regarding antifungal dosing in obese adults as well as to provide meaningful guidance on the dosing of each antifungal agent in obese patients.
The pharmacokinetic evidence regarding dosing antifungal agents in obesity is limited. Fluconazole’s volume of distribution (VD) is influenced by BMI. Therapeutic drug monitoring (TDM) studies provide some insights into dosing voriconazole in obesity, but not with posaconazole. Isavuconazole seems to be unaffected by weight. The available data for echinocandins suggests that increased doses are likely necessary in obese patients. TDM may be beneficial, particularly for azoles when available in a timely manner.
Fluconazole and voriconazole dosing should be based on total body weight and adjusted body weight, respectively. Posaconazole may have reduced exposures in obese patients, but data on its new dosage forms is lacking. Isavuconazole appears unaffected by weight. Echinocandin doses likely need to be increased in obese patients, but the exact weight and dosages remain elusive.
KeywordsObesity Antifungals Fluconazole Voriconazole Posaconazole Isavuconazole Caspofungin Micafungin Anidulafungin Echinocandin Triazole antifungal
Compliance with Ethical Standards
Conflict of Interest
The authors declare that they have no conflicts of interest.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance
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