Effect of Antifungals on the Intestinal Microbiome - a Randomized, Controlled, Proof-of-concept Trial

The goal of this clinical trial is to learn how the antifungal drug fluconazole affects the gut microbiome and immune system in healthy volunteers. The main questions it aims to answer are: * Does fluconazole change the gut bacteriome and mycobiome composition after 14 days of treatment? * How long do these changes last (4 weeks and 6 months after treatment)? * Does fluconazole affect the body's immune responses, such as blood cell activity and antifungal antibodies? Researchers will compare two groups: participants who take fluconazole for 14 days and participants who receive no intervention. Participants will: * Either take one fluconazole tablet (200 mg) daily for 14 days, or receive no treatment * Provide stool samples and blood samples at several timepoints * Return for follow-up visits up to 6 months after treatment This study is conducted at Amsterdam UMC, location AMC, with a planned enrollment of 50 healthy male volunteers aged 18-35 years.