Study aim: Comparison of multiple with once-daily nystatin regimens in prevention of oropharyngeal candidiasis in kidney transplant recipients Design: This open-label clinical trial with parallel-group and phase 3 study will be conducted on 40 patients. Randomization will be performed using Random Allocation software. Settings and conduct: In this study, kidney transplant patients hospitalized in Urmia Imam Khomeini Hospital will be included in the study. 40 patients will be divided into two equal groups. In one group, patients will receive 30 cc of nystatin once daily, and in the other group, 10 cc three times a day for one month. The study will be conducted without blinding. Participants/Inclusion and exclusion criteria: Patients undergoing kidney transplantation and treatment with immunosuppressive drugs will be included in the study. The main exclusion criteria are receiving antifungal medication due to fungal infection other than the mouth and throat, intolerance to nystatin, and non-adherence to the prescribed medication regimen. Intervention groups: Participants in the first group will receive nystatin oral suspension 30 cc once daily for at least one month or until the prednisolone dose is reduced to 10 mg/day or less. Participants in the second group will receive nystatin oral suspension three times daily, 10 mL each time. All patients will instructed to keep the medication in the mouth for at least one minute before swallowing and to avoid eating or drinking for 30 minutes afterward. Nystatin prophylaxis will be done on the first day after transplantation. Main outcome variables: Oropharyngeal candidiasis