CHIN RUBBING IN CATS
Most cats enjoy having the sides of their chin rubbed and scratched. They also rub their chin vertical surfaces - door frames, table and chair legs, etc. In addition to feeling good, this action also deposits pheromones on the rubbed-on surface. Pheromones are special scent molecules that function in animal-to-animal communication. Chin pheromones in cats are thought to be "happy" pheromones.
If you regularly scratch your cat's chin you will probably make him or her very happy. You can also make some practical use of chin scratching by extending the area you scratch. During a scratching/rubbing session include the front of the nose and the bridge of the nose. Slide your finger inside the lips briefly and massage the gums. Run your fingers from the chin up to the ears and massage those.
Go gradually; do not overwhelm your cat by trying to scratch and rub these areas all at once. Expand your area a little bit and monitor your cat's response. As he or she becomes more and more interested in what you are doing, you can progress more quickly, until you are scratching an rubbing the entire head and getting a happy response.
At this point you will probably have desensitized your cat to this kind of handling to the point where you can examine and medicate the mouth, ears, nose, and eyes relatively easily. "Embed" the task in the pleasant experience by scratching/rubbing until your cat is happy, then quickly do what you need to do, then return to the scratching/rubbing.
We do not recommend trying this with cats that will not accept some gentle chin scratching as a happy thing. Also, some cats can become overstimulated by something that starts off happy, and they will scratch or bite; for some cats, "too much of a good thing" is possible, so always pay careful attention to how your cat is responding to what you are doing.