Hi.
Welcome to HEALTHCARE MAGIC..
I have gone through your query and can understand your concern..
As per your complain black discolouration of tongue can be due to a condition known as
Black Hairy tongue and can be due to a number of causes like overgrowth of bacteria or fungus, food debris accumulation, taking medication containing
Pepto Bismol, long term intake of soft foods, not cleaning the tongue often, staining of the tongue with some medication or mouthwash etc..
I would suggest you to maintain a good hygiene status like cleaning tongue with a tongue scraper, using a soft toothbrush to scrape your tongue, gargle with 1:1 solution of
hydrogen peroxide and water, chew hard food like carrots and apple, feeding with ample of fluids..
It can take a few days to resolve and in case if it does not resolve consult an Oral Physician and get evaluated..
Hope this information helps..
Thanks and regards.
Dr.Honey Nandwani Arora.