Hello doctor, I have noticed dark (do not know if they are dark-brown, more greenish, or black) flecks in what looks like otherwise very normal stool. Can this be blood, or does blood typically only present as fully-black, tarry stool? Also, I have PKU, and my supplemental food contains 4g Ferrous Sulfate per serving. Could this cause discoloration in my stool from time-to-time?I am 43 years old with a history of anxiety, 6'2", 190, decent health. Non-smoker. Light drinker. In no pain.
Hi. Once in a while these kind of dark flecks is normal but if it is persistent then it is abnormal. Also, Ferrous Sulphate can cause blackish discoloration of stools. Blood in stools need not always be fully black, tarry stools but I strongly feel that it is due to Ferrous Sulfate. Still, I advise you get a test called Stool for Occult Blood. This test will detect any blood in your stool. If it comes positive revert back to me as you may require further tests.