Geraniol, a monoterpenoid alcohol found in essential oils such as citronella, rose, and palmarosa, has demonstrated antifungal properties in several laboratory studies. In vitro research indicates that geraniol can disrupt the cell membranes of various fungal pathogens, including Candida albicans and Aspergillus species, leading to inhibited growth or cell death. The proposed mechanisms include interference with ergosterol biosynthesis and increased membrane permeability, which are critical for fungal cell viability. Additionally, some studies have shown synergistic effects when geraniol is combined with conventional antifungal agents, suggesting potential as an adjuvant therapy.

Despite these promising laboratory findings, clinical evidence in humans remains limited. Most of the supporting data are from in vitro or animal studies, and there are few, if any, well-controlled clinical trials evaluating the efficacy and safety of geraniol for treating fungal infections in humans. Therefore, while the antifungal action of geraniol is scientifically plausible and supported by preliminary research, its real-world therapeutic value has not been firmly established. Use in humans should be approached with caution until more robust clinical data are available.