What causes a black tongue?

Black Tongue: Black tongue can be from foods or candies, from a yeast or 'thrush' infection among other rare things. If there are any other symptoms or concerns please get in to see your family doctor or dentist.

GI upset: Usually associated with GI disturbance..Hyperacidity or other..Results in enlarging of some of the papille of the tongue giving it the appearance of being black...Otherwise could also be associated with bismuth from having used pepto bismol (bismuth subsalicylate) for stomach upset.

Black tongue: Causes include medications, poor oral hygiene, smoking, bacteria with more information at : http://www.Mayoclinic.Com/health/black-hairy-tongue/ds01134.

Black tongue: Black tongue has been linked to poor oral hygiene, smoking or chewing tobacco , alcohol, cocaine, beverages like coffee, dry mouth, radiation and medications like penicillin, erythromycin , doxycycline etc, http://www.dermnetnz.org/topics/hairy-tongue/