Objective: Drug effects on the function of smell and taste are occasionally mentioned in prescription information however, most originate from anecdotal reports without even distinguishing between gustatory or olfactory deteriorations. This includes the antifungal fluconazole.
Material and methods: In a randomized, placebo-controlled, double-blind, two-way crossover study, 12 healthy men and 9 healthy women (age 26.8 ± 3.7 years) took oral doses of 400 mg fluconazole or placebo once daily for 8 days. Gustatory and olfactory functions were tested before and after the treatment using clinically validated tests ("Taste Strips" and "Sniffin' Sticks", respectively).
Results: Baseline taste scores of 12.3 ± 2.2 and 12.5 ± 1.7 for the fluconazole and placebo conditions, respectively, corresponded to normative values. Similarly, baseline (pretreatment) composite olfactory TDI scores (odor "threshold discrimination identification") of 35.0 ± 3.2 and 35.7 ± 4.3 for men and 34.8 ± 4.2 and 35.5 ± 2.8 for women during the fluconazole or placebo conditions, respectively, corresponded to normative values. Neither gustation nor olfaction was significantly affected by the fluconazole treatment.
Conclusions: The present study provided a negative result regarding fluconazole effects contrasting, for example, with those of sildenafil in a comparatively powered study [1]. Up to the tested dose of 400 mg/d, fluconazole does not have general and reproducible effects on taste and smell in healthy humans. However, it was unlikely to detect rare disturbances with the present study cohort size, and, therefore, rare fluconazole side effects on human chemosensation, as occasionally reported, remain a possibility.