When I see an older cat with diarrhea I usually think of either inflammatory bowel disease (IBD) or intestinal lymphoma. IBD is the better of the 2 to have because lymphoma is a cancer.

Unfortunately it's hard to test for these because we would need a biopsy.

However, I will often put a cat on a low dose of steroids (which is perfectly safe) and see how things go. In either case we usually see improvement. But, if it is lymphoma the improvement is temporary.

If it's IBD the cat may need to stay on steroids for life. If it is lymphoma there are chemotherapy protocols that can help somewhat.

Dr. Marie.
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