Treatment Type: Antiparasitics
Rated for: Australian Terrier / Jack Russell Terrier Mix
Bryan, Texas, United States
Posted Dec. 11, 2018
Heartgard is an ivermectin-based monthly chewable preventative. Ivermectin can be found in many formulations for many different species, but Heartgard is specifically formulated for dogs. This formulation of ivermectin is FDA approved for only heartworm prevention in dogs. This formulation works as a preventative because it kills the larval stage of the worm that is transmitted to the dog by the mosquito. If a dog is tested negative for heartworms before it is put on preventative, the monthly dose of Heartgard kills any larva introduced to the dog before the larva can complete its life cycle into an adult worm. This medication is also sometimes used for the treatment of adult heartworms. When ivermectin and an antibiotic, doxycycline, are used together, it decreases the ability for adult worms to replicate and weakens the adults that are already living in the dog’s heart chamber.
This drug has been extremely effective and safe as a preventative, especially in geographic areas with high incidence of heartworms. The dogs really enjoy the beef flavored chewable and typically take it like a treat, especially if they are food motivated. If your dog has a confirmed food allergy to beef, however, the flavoring of the medication may cause some GI upset or skin itchiness, as it did in my dog.
This drug is also safe for use in dogs with the MDR1 mutation, which is typically in herding breeds. If you know that your dog is MDR1 mutation positive, Heartgard is a very low dose of ivermectin and is SAFE for your dog.