Hi. Thanks for your query. Noted the history and understood your concerns: Diarrhea followed by gray colored stools alternating with brown color may not be the cause of concerns unless proved by the investigations: I would advise you the following in such a situation: Get the stool tests done particularly for stercobilinogen. Full liver functions and to be repeated after a few days. Ultrasonography of the abdomen to start with, Contrast enhanced CT scan of the whole abdomen and MRCP if indicated to see if there is a cause for development of obstructive jaundice. If such a thing is identifies, further tests of ERCP that is endoscopic retrograde cholangio-pancreaticography should be done for diagnosis and treatment too. May need Cholecystectomy too. If all the tests are normal, there is nothing to worry about such color changes in the stool.