Brief Answer:
Oral yeast infection recurrent may need oral antifungals.

Detailed Answer:
Hello dear, welcome to Ask a doctor service. I read your query and here is my advice.
It looks like you are suffering from recurrent yeast infection of mouth.
It may be caused by overuse of antibiotics, low immunity due to several diseases or chemotherapy, poor fitting oral dentures, smoking, diabetes etc.
If anyone of these is found on you, fixing this problem will improve the oral thrush.
Also you can use lactobacillus supplements to help reestablish the oral flora.
Using backing soda to clean tongue can help.
Use apple cinder vinegar.
Again may try nystatin.
If still persists your doctor may give you oral antifungal treatment with duflucan.

Hope I have answered the question. Let me know if I can assist you further.

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