hi since you have pain while passing stool , apply cream based lox ointment for applying at ur anus ten minutes before for three times a day . also take more of liquids and fibre diet . take syrup lactulose 4tsf thrice a day for five days for loose stool . tab nicip ds for two times a day . please sit in warm water putting ur anus dipped in it in a tub. u will be surely olrite .

Hello.... Surgery is usually necessary to treat an anal fistula as very few heal by themselves...., fistulotomy is the most commonly done surgery, doctor cut open the whole length of the fistula, from the internal opening to the external opening to flush out content ,fistula heals on its own by 2-3 months .consult general surgeon.