Does her food have artificial colors? I would not use anti-fungal but you could try peroxide on a rag or paper towel. It won't hurt her if she gets any in her mouth.
I found this info:
Your Welcome, I would suggest trying to clean the stain with peroxide as well like Jane suggested, and then when you feed her treats, watch to see if it comes back after shes eating her treats. or maybe it will take a few times of eating her treats before taking her for a teeth cleaning.
Sounds like a good plan Natalie:)
Thanks Jane :)
Do you have a picture? Dog's saliva can turn their fur pinkish/rust colored...is it possible she's just drooling more than usual?