hello thank you for trusting HCM dear It’s normal for your stool to change color. You likely have a varied diet and changes in your diet impact your stool. But yellow stool, sometimes called pale stool, can also indicate a number of health problems. possibilities causes like gallbladder and liver problems, disorders of pancreas, celiac disease, Gilbert syndrome, stress etc...sucralfate can cause dark brown stools. but please consult your doctor he will examine and treat you accordingly. I think I answered to your question if you have more questions feel free to ask. take care