Heartgard contains ivermectin and pyrantel pamoate, while Drontal contains praziquantel which is needed to kill tapeworms. Pyrantel pamoate kills roundworms and hookworms living in … Instead of … I'm so glad! You are very welcome. This book, written by an ex sufferer of skin parasites, is the most comprehensive resource you will find regarding Morgellons, Collembola, and Strongyloides. You will even learn how to order in restaurants without feeling like a leper. Don’t order heartworm pills online from places like PetMeds. You can’t give your pet preventative medication if he is already infected with heartworm. If your pet has roundworms, he may show these signs: Your vet will prescribe deworming medication to get rid of these worms. //-->