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I hope this the right way to post a health problem for which I need advice. My 14 1/2 year old Westie Lucy has had bouts of throwing up food or mix of food & yellow liquid (bile, but not the foamy stuff) over the past few months. Vets are baffled as to what could be wrong. IBS has been suggested as a possibility. What we have done so far - I cook for my dogs so we switched from chicken to turkey. OK for 6 - 8 weeks & the vomiting starts again. There are usually undigested chunks of food (sorry for being so descriptive). We have tried 2 canned foods from the Vet (I ate canned food). The current one is Science Diet Hydrolized Protein(chicken, no grains). Lucy had another bout of throwing up 3 1/2 week ago, then part of this past Saturday & all day Sunday. Took her off the canned food & back on small amounts of cooked ground turkey. She was fine for 3 days then threw up twice last night of gold colored bile & some blades of grass.. She did eat a tiny bit of ground turkey this morning.. She looks miserable after she throws up, but her appetite always remains strong. She is full of spunk & energy most of the time, chases lizards, barks at stuff, rolls in the grass, etc. As per vet instructions, we feed her 3 - 4 small meals a day & break the food up so she can digest it easier. She has omeprazole before breakfast daily & Proviable in dinner. At each occurrence of vomiting, she has been given Cerina (spell?) to stop the nausea. She has had an abdominal ultrasound that found nothing. Next, she will be having extended bloodwork to check liver, kidney & pancreas enzymes. Any suggestions as to what may be causing all this? I feel so bad for her. With my recent surgery, funds are in short supply, but we will do what seems reasonable to help her feel better & tolerate food. yellow mother of the bride dresses