Hi Dear , As per your query you are passing bright yellow stool while suffering from acid reflux . Well there can be many reasons for yellow stool like :- - bilirubin and fat ( doctor has lready rule out ) - protein - undigested food - mineral salts - mucous from the digestive system - pancreatic Causes - emotional stress But in your case it seems to me that the reasons responsible for yellow stool is acid reflux . I would suggest you to avoid eating spicy and heavy meal specially at night , eat at least one hour before going to bed , take light walk after every meal and take antacid (gelusil ) after every meal . Consult gastroenterologist for proper examination . Doctor may order endoscopy , ultrasound for pancreas and X-ray of upper digestive track along with other tests . Doctor may prescribe drugs like omeprazole and ranitidine . Sometimes doctor may recommend surgery for correction of defect . Hope your concern has been resolved. Get Well Soon. Best Wishes, Dr. Harry Maheshwari