Preventive action of ketamine alone and in combination with antifungals on Candida biofilm formation in catheters

PURPOSE: This study investigates the repurposing potential of the anesthetic ketamine (KET) as a preventive agent, both alone and in combination with the azoles fluconazole (FLC) and itraconazole (ITR), against Candida spp. biofilms adhering to fragments of peripheral venous catheters. METHODS: The activity was assessed in vitro through cell viability and colonization assays of impregnated catheter segments, while morphological alterations were analyzed using scanning electron microscopy (SEM). RESULTS: KET, both alone and in association with ITR, significantly reduced (p < 0.05) the adherence of C. albicans to the impregnated fragments. Furthermore, the combinations KET + FLC and KET + ITR frequently exhibited greater efficacy in reducing biofilm viability than the agents used individually, suggesting additive/synergistic interactions. SEM revealed structural damage to the treated fungal cells. CONCLUSION: These findings indicate that KET exhibits preventive activity against Candida spp. biofilms, including on catheter surfaces, and may enhance the activity of azoles, positioning it as a promising candidate for repurposing in the treatment of biofilm-associated fungal infections.