Have your tried a culture or a trach wash or anything to try and find out what exactly it may be causing it and what antibiotics may work? You can also try to check and see if your kitty is resistant to the antibiotic you are using or if it's being caused by polyps or something. You could also try testing for Bartonella henselae. Good luck. I hope you get it figured out and your baby is feeling better soon.
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