Pet Health

How to prevent heartworm disease

Heartworm in dogs can be treated, but prevention is best.

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The good news is that most dogs with heartworm disease can be successfully treated, usually with drugs that kill adult heartworms and their offspring.¹ But heartworm treatment is a long and difficult process, so, like many other pet-related health issues, prevention is best. It’s safer, less expensive, and better for your pet!

Testing and prevention

Preventative medications are extremely effective and when given properly, on a regular basis, can prevent your pet from contracting heartworm disease. Still, even dogs on preventative medication should be tested regularly for heartworm — because if a dog is already infected with heartworms, giving him preventative medication may be harmful or deadly.²

One issue is that if a heartworm-positive dog doesn’t get tested before starting a preventative, she’ll remain infected.² However, her owner probably won’t know until she gets sick enough to show symptoms. Immature heartworms remain undetected, and pets may appear healthy.² Dogs should be tested before they start heartworm preventatives.² Heartworm preventatives do not kill adult heartworms in already infected dogs.² Also, if microfilariae (infected heartworm larvae) are in the dog’s bloodstream, the preventative may kill the microfilariae suddenly, triggering a shock-like reaction — and possibly death — of the dog.²

And remember, year-round heartworm protection is only as good as your diligence in remembering to give your pet the prescribed medication.

More like this

Can I get heartworm from my pet?

Heartworms are transmitted by the bite of an infected mosquito.² Pets can’t catch heartworm from each other, and you can’t catch it from them. Many heartworm preventive medicines, including SENTINEL® Spectrum® Chews and SENTINEL® Flavor Tabs® also provide effective protection against other internal parasites, including hookworms, roundworms, whipworms and tapeworms.^3,4 This is just one more reason to talk to your veterinarian about regular parasite prevention for your dog.

References

Heartworm. Companion Animal Parasite Council. https://capcvet.org/guidelines/heartworm/
Keep the Worms Out of Your Pet’s Heart! The Facts about Heartworm Disease. FDA.gov. https://www.fda.gov/animal-veterinary/animal-health-literacy/keep-worms-out-your-pets-heart-facts-about-heartworm-disease
Sentinel^® Flavor tabs^®. https://merckusa.cvpservice.com/product/view/1047561
Sentinel^® Spectrum^® Chews. https://merckusa.cvpservice.com/product/basic/view/1047562

Important Safety Information

SENTINEL^® SPECTRUM^® Chews (milbemycin oxime/lufenuron/praziquantel). Dogs should be tested for heartworm prior to use. Mild hypersensitivity reactions have been noted in some dogs carrying a high number of circulating microfilariae. Treatment with fewer than 6 monthly doses after the last exposure to mosquitoes may not provide complete heartworm prevention. For complete product information refer to the product insert.

SENTINEL^® FLAVOR TABS^® (milbemycin oxime/lufenuron). Dogs should be tested for heartworm prior to use. In a small percentage of treated dogs, digestive, neurologic, and skin side effects may occur. For complete product information refer to the product insert.

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