They don't combine the two because of stomach upset and gastric problems, which seem to be a far less concern in this case. If they still don't want to use an NSAID, Tramadol is often used with pred for puppers (not sure about kitties). The heavy duty pain meds are also possible, so there shouldn't be any reason for him to be in pain or discomfort. You might have to push strongly for meds; I often have.
I'm sorry he's feeling so bad, and you're right--sometimes they feel like they've been a part of you forever, even when it's only been weeks or months. You made a serious difference to Barney Boy!!!!
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