Drontal Chewables are tasty chewables made from real liver that treat your dog for all major species of gastrointestinal worms including roundworm, hookworm, whipworm and tapeworm. Also controls shedding of Giardia oocysts.Treats and controls all major intestinal worms including roundworm, whipworm and hookworm. Controls tapeworms, including the hydatid tapeworm. Controls shedding of Giardia oocysts