Hi..you need to visit a dentist or dermatologist first. They will take smear layer from tongue and send it to pathology lab for fungi detection. There are lot of fungi and the most common being Candida. Antifungal mouthwash can be started only after doctor's advice.
Regards
U need to visit your dentist, since u might be havin' dental plaque/calculus problem (indicator here bein' bad breath), u might need to get full mouth scaling...., n use some good mouthwash after u brush ur teeth 'n otherwise often usage of latter......
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