So sorry to hear that Snickers isn't feeling so good and having problems eating.
That Snickers liked the baby food gives you two clues:
1. It is soft and therefore is unlikely to hurt the mouth.
2. It is bland and easily digestible and therefore may be less likely to trigger intestinal discomfort.
Your current vet is very remiss in failing to check for gingivitis or other dental issues. It's the number one thing to check for all diabetics as they are very prone to dental/mouth issues.
Research any potential side effects of the treatment she was prescribed recently. Based on the clinical signs you describe I recommend you look for gastrointestinal side effects in particular. Good sites include:
www.drugs.com
http://marvistavet.com/pharmacy-center.pml
http://www.peteducation.com/index.cfm?c=1
As others have already suggested above, so many of Snickers' clinical signs point to pancreatitis as a potential issue. IBD is another avenue to explore. If Snickers were mine I'd look to get a vet to treat 'as if' nausea was a problem and look to get a prescription for ondansetron (and possibly a dose or two of Cerenia on top, especially if she vomits). If nausea is the problem the aforementioned meds work very, very effectively. I'd also recommend
When you get the test results, look at kidney, liver, B12/folate, enzyme and cholesterol markers for clues. Most importantly look for results for SNAP fPL or Spec fPL; these are the most commonly used tests for pancreatitis. If you don't see results for these tests ask the vet for the specific name of the test(s) the vet commissioned for pancreatitis so that you can make sure Snickers really has been tested for it. (There's at least one lab that offers an equivalent test to the IDEXX Spec fPL but I can't remember the name.)
It might be worth trialling a course of buprenorphine to see whether there is any occult pain. Also, if Snickers responds to the bupe then the reduction in stress and pain could help speed healing of any underlying issues.
It must be very frustrating for you that home testing has not proved feasible in Snickers' case; it could give you so much valuable information. Try home urinalysis if you can; it's better than no testing at all.
Sending prayers and positive vibes for Snickers, Dre. I know how very deeply you love her and I know all too well how heart-wrenching it is to see someone you love so much feeling so poorly. I feel for you from the bottom of my heart and I fervently hope that you'll get to the root of the problem really quickly so that Snickers will be able to eat properly and feel better very soon.


Mogs
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