Brief Answer:
Self care/ specialist consultation would help.

Detailed Answer:
HI, XXXXX.
Thanks for the query. I have read it & understood your concern.
White coated tongue is collection of debris, bacteria, dead tissue ( being entangled between inflamed & enlarged papillae.. the small raised projections.. on tongue,)
It can be due to many causes like poor oral hygiene/ dry mouth/ eating tobacco, smoking/ taking alcohol/ mouth breathing/ fever./ tongue irritation by broken tooth or ill fitting denture./ Antibiotic consumption.
Most of above causes lead to inflammation & thickening of tongue papillae.. which alters the normal bacterial flora of tongue to facilitate infections like- oral thrush/ cancer/syphilis or aids.
* IN your case as per information provided it seems to be due to prolonged antibiotic consumption/ ill fitting dentures with with oral thrush..
Oral thrush is a fungal infection of tongue which is characterized by creamy white patches of tongue, may spread to mouth. It causes cottage cheese like appearance of tongue, which also becomes red, burning, bleeding on touch & loss of appetite.
* Self care-
- Observe good oral hygiene,
- Avoid tobacco, smoking, alcohol.
- Take lot of water / liquids to avoid dry mouth.
Apply over the counter anti fungal ointment like Candid oral along with XXXXXXX ointment two- three times a day after mouth gargling with warm water.
- Take mild purgative in case of constipation.
- Take over the counter B complex pills / lactobacillus containing preparation .
* But if the condition keeps on recurring/ spreads beyond oral cavity/ no relief with the local treatment & persists over a prolonged period, then you need to consult a Dental surgeon for his expert examination& investigations to diagnose exclude resistant thrush. Oral anti fungal would be advised / Investigations for diagnosing & excluding more concerning causes.
I hope the answer was both informative & useful to you. Any follow up query is welcome.
Please do not forget to close the query & grade it if you are satisfied.
Thanks.

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