As veterinary surgeons we see cats for a variety of problems. A lot of these can be related to stress. Yes, our feline friends are very complex. Some of the well-known diseases that are stress-related are: blood in the urine, spraying, excessive grooming leading to furballs, bald patches and significant skin lesions; to name a few.
The good news is that for some cats all you have to do is improve your cat’s environment to make them happy. No medication, no diet changes.
To help you improve your cat’s environment there is a journal article, authored by feline behavioural specialists, on improving your cat’s home environment to make them happy.