I have an appy-arabian +20 year old mare. She cribbs. Recently, the last month or two she has developed a problem swollowing. It's usually worse in the morning than the evening, there is some edema noted around her lower jaw and cheeks where she is also tender to palpation. She has no place to cribb during the day, however she is let in at night due to other horses behaviors. I have had the vet out to see her 3 times. We have floated her teeth, and given her bute The last time he scoped her upper airway gave her lasix IV and dexamethosone IM this seemed to help for two days and now she is back to not finishing her grain. Please any suggestions would be greatly appreciated.

Optional Information:
Age: >12; Female; Breed: horse, appy-arabian

Already Tried:
3 vet apt. bute, lasix, dexamethasone anithystamine mashing grain/p>