Brief Answer:
Needs investigation to rule out cancerous/precancerous conditions

Detailed Answer:
Hello and welcome to Ask a Doctor service.

I have reviewed the attached photograph of the tongue and have read your query carefully.

Since this is going on for 3 years, it needs to be properly examined and investigated further to rule out serious causes.

There are many causes for whitish coat on the tongue which include,

1. Oral thrush (fungal infection),
2. Geographic tongue (usually as a result of iron deficiency anaemia)
3. Oral lichen planus
4. Leukoplakia (pre cancerous condition)
5. Tongue cancer
6. Benign hypertrophy of the filliform papillae (increase in the size of the fine finger like projections on the tongue).

For a change I would advice you to stop any medicines you are taking for this and use the tooth brush to brush your tongue once a day in the morning. Do not use the tongue cleaner.

Stop even Listerine.

Do not drink any carbonated beverages.

Please do get your blood tested to see for iron deficiency anaemia and syphilis.

This is a major problem and should be covered by your insurance, consult a surgeon and get a biopsy done to rule out cancerous conditions.

The scrapings from the tongue also need to be looked under microscope to see if it is due to fungal infection.

A biopsy of the tongue will give the final diagnosis in your case, so please do consult a general surgeon, or a Head and Neck surgeon and get the biopsy done.

I completely understand your frustration, this is a major medical problem and should be covered by your insurance, so talk to the doctor and the insurance people they will help you out.

You can start taking iron and multivitamin supplements in the meanwhile and see if it helps.

I hope I have been able to direct you in the right direction, please do write back to me if you have any further questions.

Wishing you speedy recovery and good health.

Best wishes.

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