You're speaking to Dr. Michael Salkin. Welcome to JustAnswer. I'm currently typing up my reply.
Thank you for your rescue efforts. Supplementation with oral enzyme replacement therapy is the hallmark of treatment. No supplements other than vitamin B12 need be considered. B12 is only needed if my patient is B12 deficient (serum B12 levels are easily assessed by our reference labs) but 80% of dogs with EPI are B12 deficient. Vitamin B12 is absorbed mainly through the ileum - the "middle" of the small intestine. Malabsorptive disorders aren't uncommon in associated with maldigestive disorders such as EPI; hence, so many EPI patients being B12 deficient.
Oral antibiotic therapy such as with tylosin is indicated in patients that don't respond to enzyme replacement therapy. That doesn't appear to be the case with Bella, however. A premium highly digestible maintenance diet is sufficient and dietary fat restriction is neither necessary nor recommended. Please respond with further questions or concerns if you wish.
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