Diflucan is a tablet you swallow to treat vaginal yeast infections caused by yeast called Candida. Diflucan is used to treat fungal infections, yeast infections, urinary tract infections, peritonitis, pneumonia, and cryptococcal infections. Diflucan is different from other treatments for vaginal yeast infections because it is a tablet taken by mouth. Do not take Diflucan, generic Diflucan, or Fluconazole if you are taking Cisapride.