Hi , I'm James DVM MRCVS and would like to help you with your question
Sorry to hear about Arnie not eating his food .
There are several options we need to explore for us to get to the bottom of the problem
1. Since he had his teeth out 3 weeks ago - maybe one of the following had occurred
* there is still an underlying infection or inflammation going which causes him sever pain
* perhaps in the process of taking all his teeth out - one tooth was not taken out fully (broken in the process) and thus is left behind causing great pain
* Maybe there is some injury to the soft tissue left behind.
2. Since Arnie has undergone surgery and is not a young lad - There are times side effects cause by the anesthesia and anesthetic agent - things like inflammation of the stomach or intestines , mild kidney disease and others . it could be that it triggered and underlying disease such as Pancreatitis or other pre existing condition.
What I would advise is the following :
pay a visit to your vet for him to better explore Arnie's mouth for any of the things I have mentioned . he can perform an Xray ray for a better look as well. Perform a blood test to see that Arnie is otherwise all right .
in one of these exams - Arnie's problem will be found and you would be able to treat it .
I hope this helps.
If you have any further questions - let me know and I shall do my best to help.
All the best to you both
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