I asked the doctor about me giving Emma Mae water and it filling her up so she isn't hungry. Dr. Said that cannot happen. Cats systems are set up that way for that to happen. Also added her about Pepcid, she said it works on dogs but wouldn't recommend it for a cat.
Re: water intake for cats http://www.animalendocrine.info/2011/10/daily-water-requirements-and-needs-for.html
As far as the Pepcid, did your vet say why she wouldn't recommend it for a cat because there a lot of vets who recommend its use. http://www.petmd.com/pet-medication/pepcid is just once source citing its effectiveness in cats.
Pepcid helped my cat with inflammatory bowel disease when he was very ill. I gave it to him every day along with the prednisolone until his pain went away and his appetite was stable. He's been stable for a couple years now. Thank goodness.
Here is an excellent resource re: IBD. Cornell is one of the premiere vet schools in the country. http://www.vet.cornell.edu/fhc/Health_Information/brochure_ibd.cfm