my 18 yr cat had large appetite,then have puddles of diarrhea.yellow turned to brown later on.she have it 3 times a day,months .i took her to the pet hospital they couldn't find nothing wrong with her,,gave her few medicines stopped diarrhea,but it didn't quit then she had some red blood in it.,she got very skinny from diarrhea and died on my couch all four legs spread out ,two loud cries.,mouth been opened.sad too I will miss her,i tried best I could to save her.