I've had hyperplastic chronic thrush, the kind that cannot readily be wiped off and may appear discolored because of staining from food and drink, for over two years. My ENT has had me on nystatin which never got rid of it but kept it from getting worse. A dentist suggested I try a thin coat of Monistat nightly and my tongue has never looked or felt better. It's in the nystatin family only stronger, it has an oil base and stays on tongue longer. I was told the only time nystatin is helping is the time it's in contact with tongue, in my experience not long.
I hope this helps someone and you all have a wonderful, healthy New Year. There is life after OC and it's fantastic because we appreciate it so much more after all we've been through.