Cestem Dewormer Large Dog is a broad-acting wormer against roundworms, tapeworms, hookworms and whipworms in large dogs. Due to the risk of infection in humans and animals, preventive deworming is recommended. It is best to treat an adult dog for worms 3 to 4 times a year. Worms can disrupt body functions and affect your pet\'s health. They absorb nutrients that the dog urgently needs to stay healthy and fit. Cestem contains the active ingredients pyrantel, febantel and praziquantel.