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HEARTGARD | Heartworm Disease | About Heartworm Disease and Your Dog

Your dog deserves protection against heartworms – and it's easy to do.

Heartworm disease can affect dogs anywhere. The disease has spread to every corner of the U.S. and hundreds of thousands of cases are reported every year1. Heartworm disease can be prevented by administering an effective heartworm preventive year-round. Protecting your dog against heartworms and heartworm disease can be convenient, simple, and affordable.

How can heartworm disease be prevented?

Pet owners can use HEARTGARD® Plus (ivermectin/pyrantel), the #1 veterinarian-recommended preventive available for dogs2 to help prevent heartworm disease. In an unprotected dog, heartworm larvae, transmitted by a bite from an infected mosquito, mature and migrate to the heart. Year-round treatment is recommended by the American Heartworm Society and the Companion Animal Parasite Council3.

Why shouldn't I wait and see if my dog develops heartworm disease? Can't my veterinarian just treat it?

It's important to understand that heartworm disease has usually reached an advanced stage by the time your dog shows signs of illness, and it is possible that the dog may never show signs of an infection. Treatment is risky, expensive, and may not be effective. The approved treatment involves the use of a product containing arsenic, your dog will be kept inactive during treatment, and you will have to keep your dog inactive for weeks afterward – and despite these measures, treatment may not be successful.

Click here to learn more about why heartworm disease prevention is the most sensible way to protect your dog's health.

How does my dog get heartworms?

Learning about how heartworms are transmitted will help you understand why it is important to protect your dog from becoming infected. Point to each illustration on the diagram below to learn more.

Adult heartworms grow up to 12 inches long and reproduce. Infected dogs infect more mosquitoes, which can then infect additional dogs.

See the HEARTGARD Plus FAQs for answers to more questions about heartworm disease and HEARTGARD Plus.

IMPORTANT RISK INFORMATION: HEARTGARD is well tolerated. All dogs should be tested for heartworm infection before starting a preventive program. Following the use of HEARTGARD, digestive and neurological side effects have rarely been reported. For more information, contact your veterinarian or click here for important safety information and full prescribing information. Accessed on February 14, 2008.
2MDI data on file at Merial
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