Urgent need advise, not eating at vet being syringe fed

My chinchilla developed an eye infection. She is 17 and developed a chronic eye infection about 14-15 about every 6 months. She was treated with eye drops and it would clear up after treatment. She has been seen by 3 vets over this span and had x-rays all instances of tooth problems have been ruled out.

This time her eye shut when the infection started which was new. The doctor prescribed Baytril this time around since it seemed the infection was more serious. About 6 days into treatment I noticed she was no longer eating or pooping.

I took her to the vet and they have had her for 3 days now. She is on Baytril still and pain medications and being Syringe fed. Her teeth and all her vitals are normal but she is showing almost no interest in food and when she poops its just a tiny one maybe about 1/16th the size of normal. She doesn't even show interest in her favorite treats.

Any ideas or advice are welcome.