Hi Ariadne, I see your post was a couple days ago, I hope things may be going better. Anorexia is very common in cats with pancreatitis, even more so than vomiting. The mainstays of treating it are fluid therapy, appetite stimulants and sometimes pain medication. There are some cats I’ve been able to treat successfully with office visits but others require hospitalized care. Unlike in dogs, high fat diets are not the underlying cause of pancreatitis in cats, so we can feed even small meals with something as simple as chicken/liver baby food, fancy feast, anything like that. Hepatic lipidosis can be a concern and complication like you mentioned. Treating nausea is important too, as underlying nausea not only contributes to food refusal but may turn cats off to what is being offered not just now, but in the future as well, creating a need to constantly try new things.
For longterm management, it’s important to understand that many cats with pancreatitis also have a component of inflammatory bowel disease that usually stems from a dietary protein allergy (or allergies). Some cats may have concurrent bile duct disease as well. If they have all three (pancreatitis, IBD, cholangiohepatitis), this is called triaditis (though most cats have only two at a time).
All three areas (pancreas, bile ducts, small intestine) share a common duct system and so intestinal inflammation can often contribute to concerns in these other areas. Diarrhea itself is not a common sign of pancreatitis alone in cats (diarrhea can have a multitude of causes), but chronic diarrhea can be seen with IBD (as can vomiting) and a cat with IBD could develop pancreatitis as well.
After your cat recovers from the pancreatitis flare, the longterm thing to think about would be a hypoallergenic diet, either a novel protein diet or a hydrolyzed protein diet. Some cats also need steroid therapy, but many can be managed on diet alone, at least initially.
I hope he’s been able to recover more. I’ve seen some cats make a quick turnaround, while others may take as long as a week. TLC, constant care, and frequent rechecks are commonly needed.