A cat that keeps spitting on its mouth may be caused by poisoning, oral inflammation, or improper diet. First, you must confirm whether the cat has swallowed the medicine by mistake. If the cat has just eaten the anthelmintic medicine, it may be too bitter. If spitting occurs, the cat’s condition needs to be observed. If the cat keeps foaming at the mouth, it should be sent to the pet hospital for examination and treatment in time; if it is oral inflammation, the cat’s diet needs to be adjusted and nutrition supplemented.