What is heartworm disease?

Heartworms are a type of parasite that live within the large blood vessels of the heart that supply the lungs. Heartworm disease occurs when adult heartworms cause inflammation and blockages in those vessels. This can lead to stress on the heart and lungs, causing signs such as coughing, exercise intolerance, difficulty breathing, and even death.

How do pets get infected with heartworm?

Microfilaria (heartworm larvae) are transmitted by mosquitoes. A mosquito bites an infected dog/cat and acquires some of these tiny larvae. When that mosquito bites another dog/cat, the larvae are transmitted to the animal through the bite wound. Over a period of 6-7 months, the larvae mature into adult heartworms that settle into the blood vessels in the lungs.

How do I prevent heartworm disease in my dog?

Heartworm preventative medications are designed to kill the microfilariae in your pet’s bloodstream to prevent them from maturing into adult heartworms. There are multiple options in terms of preventative products available for your dog. Regardless of which product you choose, it is recommended to provide heartworm protection year-round.

  • ProHeart 6 is an injectable preventative that is repeated every 6 months. It provides continuous protection without the need to remember to give a monthly medication. ProHeart 6 is safe for use in dogs 6 months of age and older. ProHeart 6 also provides protection against an intestinal parasite (hookworms).
  • Heartgard Plus is an oral chewable preventative that is given once monthly. It is safe to use in dogs that are at least 6 weeks old. Heartgard also provides protection against two intestinal parasites (hookworms and roundworms). There are other oral heartworm preventatives available that work similarly to Heartgard Plus.
  • Revolution for dogs is a topical preventative that is applied to the skin between the shoulder blades once monthly. It is safe to use in dogs that are at least 6 weeks old. Revolution for dogs also provides protection against fleas, ear mites, scabies mites, and the American Dog Tick.

*All dogs are required to have a negative heartworm test (within the last year) prior to starting a heartworm preventative medication.

What about cats?

Unfortunately, cats can get heartworm disease too. If your cat goes outdoors at all, it is recommended to have him or her on a heartworm preventative.

  • Revolution for cats is a topical preventative that is applied to the skin between the shoulder blades once monthly. It is safe to use on cats that are at least 8 weeks old. Revolution for cats also provides protection against fleas, ear mites, roundworms, and hookworms.

The list of products above is not a comprehensive list. These are the preventatives that we use most commonly at Country Hills Pet Hospital.