What happens if a cat is hit?

A hit cat may show a stress response, because cats are naturally sensitive and timid; after being hit they are very fearful and may vomit, diarrhea, lose appetite, and become lethargic.

Also, a hit cat may develop a psychological shadow, hissing, puffing up, or hiding in a corner when it sees the person who hit it. If that person reaches to pet it, the cat may scratch or bite.