Suggest Treatment For Infection In Genital Area

my daughter is six years old,she had some infection in her genital area,it was like a fissure.also she had problem passing stool.Doctor said she has obstipation ans suggested lactulose for drinking and ketoconazol creme for applying. Her condition improved with the above medication, but now its over eight months and when I stop putting ketoconazol a white fungus type come in her genital area.I am very worried now, the medicine has severe side effects ,but if I discontinue she is again facing problem.Is there any remedy for her condition,also for how long can I give her these two medicines