SoonToBeThinKAT 67 Posted February 7, 2013 I had an issue with a black tongue when I was taking my Centrum chewable vitamins. When I changed from that it went away. Hope that helps some Share this post Link to post Share on other sites
NurseGrace 509 Posted February 8, 2013 yep oral Iron will also make your tongue black. I have had a problem with a coating on my tongue but its from the low carb diet. my tongue scraper and tongue brush have been my friend since the preop diet started. Share this post Link to post Share on other sites