Objectives <p>Oral candidiasis (OC) is a fungal infection caused primarily by <i>Candida albicans</i>. Treatments are associated with side-effects and toxicity. Bipolar water (BW), a novel functional water with antimicrobial, biofilm-disrupting, and wound-healing properties, offers a promising alternative therapy.This clinical trial aimed at evaluating the efficacy and safety of BW in OC treatment.</p> Methods <p>This randomized controlled trial enrolled 72 participants diagnosed with OC. Participants were randomized into four groups: BW mouthwash at two concentrations (HOCl at 40–55&#xa0;mg/L, group 1; HOCl at 120&#xa0;mg/L ± 20&#xa0;mg/L, group 2), BW mouthwash (HOCl at 40–55&#xa0;mg/L combined with nystatin tablets, group 3), and control group (CG; nystatin tablets and sodium-bicarbonate mouthwash). Efficacy was evaluated by clinical efficacy, mycological efficacy, and comprehensive efficacy (defined as a combination of clinical and mycological responses), and safety was assessed by adverse event (AE) monitoring. <i>P</i>-values were considered significant if &lt; 0.05. The treatment schedule was as follows: BW mouthwash (groups 1, 2, and 3) was used five times a day, nystatin was taken three times a day (group 3), and sodium-bicarbonate mouthwash was used three times a day in the control group.</p> Results <p>At 14 days, groups 1 and 2 demonstrated percent clinical response of 76.5% and 64.7%, respectively, which was comparable with that in the CG (64.7%). Values for mycological response were 47.1% and 37.5%, with clearance of 23.5% and 18.8%, respectively. The CG achieved a significantly higher percent clearance (76.5%). With respect to comprehensive efficacy, there was no significant difference between the three groups (88.2%, 82.4%, and 88.2% for groups 1, 2, and 3, respectively), but percent cure was higher in the CG (52.9%) than in group 1 (17.6%) and group 2 (11.8%). At 28 days, group 3 achieved the highest values for clinical response (87.5%) and cure (68.8%), marginally exceeding that for the CG (76.5% and 58.8%, respectively). There was no significant difference between the two groups with respect to clinical efficacy, mycologic efficacy, and comprehensive efficacy. BW was well-tolerated, with only mild AEs reported (e.g., oral irritation), which did not merit treatment discontinuation.</p> Conclusions <p>BW mouthwash, as a standalone or adjunctive therapy with nystatin tablets, is a safe and efficacious treatment for OC, significantly alleviating clinical symptoms and improving the chance of cure.</p> Clinical relevance <p>The findings of this study provide valuable evidence on the clinical benefits of BW in treating OC, and may contribute to the development of new therapeutic options for this common (but challenging) condition.</p> Clinical trial registration <p>The trial was registered at the Chinese Clinical Trial Registry (ChiCTR) under the registration number ChiCTR2400087579.</p>