I have painted over old ceramic tile but you must use an oil base enamel. If you can dull the surface by sanding it will help, but the tile surface is very tough and this is not an easy job. I also tried a chemical etch product used for preparing bathtubs for refinishing, but it did not etch the tile surface. Try contacting Martin-Senour Paint Co....the paints used for painting cars can be used for the tile. Eventually, the paint may peel in areas that are constantly wet and will require touchup.