Hello. Thanks for writing in. My name is***** and I would be happy to help you. I am not set up to do phone calls but would be happy to answer any questions you do have online. If you get a request for a phone call, it is from the website and not myself. Most likely, the odor is coming from some type of illness. We don't really see odor associated with age. Something medical is causing that. With cats, it is usually from the mouth or anus, but it can be from the skin and ears as well, especially if they are infected. With his weight loss, hyperthyroidism, diabetes, kidney failure, inflammatory bowel disease (especially if there is vomiting or diarrhea) and cancer are all potential causes. Diseased teeth and gums, stomatitis (inflammatory condition of the mouth), kidney failure, diabetres or even oral cancer can all cause bad breath. If there is some chronic vomiting or diarrhea, an infectious or cancerous cause could cause the odor. My best advice is to get him to the vet for an exam at least. Running blood work would be a very good idea. Granted, your vet probably won't find anything that can be cured. Some of these illnesses can be managed, but probably not for that long at his age. At the very least, they can give a clue as to what is going on and what his expected lifespan or prognosis may be. Sometimes that can really help in making a decision whether to let him go or not. Please let me know if you have any other questions or concerns. Hope this helps.
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