Hi.. the most common cause of having pain or burning sensation while passing stools is Anal Fissure.. this is a cut or wound at anal region.. at times it causes bleeding ... it may be associated with some growths at anal region... Anal fissures can be very effectively cured by Ayurvedic Medicines.... in chronic cases medicines may b of little help and u may need Kshar Sutra Therapy for permanent cure.. Diet plays a very important role in its management.. try to increase fibre and fruits in ur diet.. avoid oily and spicy foods.. Al d best