Tapeworms are parasites that use their hook-shaped mouth to anchor to the wall of your cat or dog’s intestines. Cats or dogs get tapeworms by ingesting flea larva. Cestex tablets are prescribed to treat tapeworm infections in cats and dogs. Cestex is a safe and effective dewormer that causes the tapeworms to detach from the host, which are then destroyed in the digestion process. Cestex is a single dose tablet that is minimally absorbed by the intestines resulting in limited side effects.