No, you should never use human toothpaste on your cat’s teeth. Human toothpaste may contain ingredients harmful to cats, such as xylitol, a known poison to cats and dogs. Human toothpaste may also contain fluoride or peppermint, which can be poisonous to cats when ingested. Instead, use specially formulated toothpaste for cats like C.E.T. Enzymatic Dog & Cat Poultry Flavor Toothpaste, designed to be safe to swallow while reducing plaque.