How to Treat Heartworm Disease in Dogs

Heartworm disease is a serious, sometimes life-threatening condition that can affect pets and even people. This article will help you understand what heartworm disease is, how it’s diagnosed and treated, how to prevent it, and how to protect your other pets from heartworm disease.

What is heartworm disease?

Heartworm disease is caused by a parasite that is transmitted to dogs by mosquitoes. The heartworm larvae enter the dog’s body through the bite of an infected mosquito and then travel to the lungs, where they mature into adult worms. Adult female heartworms can grow up to 12 inches long!

Heartworms live in the right side of your dog’s heart and cause damage there. They also can spread to other parts of the body, including major blood vessels in his neck, chest cavity, and abdomen.

Heartworm disease is serious—it can lead to an enlarged heart (cardiac enlargement), congestive heart failure, fluid buildup around his lungs (pulmonary edema), or death if left untreated. Left untreated, it may also affect your pet’s quality of life due to symptoms related to its presence such as coughing/difficulty breathing or lethargy/weakness.

What are the signs of heartworm disease?

The signs of heartworm disease can be subtle at first, but they can also quickly become severe. Some common signs of heartworm disease include:

  • A lack of energy and appetite
  • Coughing, especially after exercise or drinking water
  • Breathing problems that are worse at night
  • Weight loss or a decrease in muscle mass (aka skinny fat) due to anemia
  • Vomiting and/or diarrhea
  • Joint pain and stiffness
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Heartworm disease can also cause skin lesions such as baldness, redness, swelling around the eyes, scratching or biting areas of hair loss (which may bleed), discoloration on the ear tips and nose tip due to blood clots behind them (frostbite-like appearance). The lymph nodes under your dog’s jaw will be swollen when he has this illness too!

How is heartworm disease diagnosed and treated?

If you suspect that your dog has heartworm disease, contact a veterinarian. There are several diagnostic tests that can be performed to assess the presence and severity of heartworm disease.

The first step in treating a dog with heartworms is to administer an injection of a prescription medication called Heartgard (ivermectin) or Interceptor (milbemycin oxime) once per month for six months to kill off any adult worms currently residing in their body. In order to prevent reinfection with new larvae, it’s also important to give them an oral preventive medication every month for at least six months, though this may be changed after discussion with your veterinarian.

How can I prevent heartworm disease and other parasites in my dog?

  • Use a preventative medicine.
  • Keep your dog clean and free of fleas, ticks and other parasites.
  • Keep your dog’s weight in check. Overweight dogs are more likely to contract heartworm disease than dogs at a healthy weight.
  • Make sure your pet is up-to-date on its heartworm test, vaccinations and deworming medication (if needed). This can be done by contacting your veterinarian or local animal shelter.
  • Avoid mosquito-infested areas during the summer months when mosquitoes are most active, especially if you live in an area where these types of insects are present year round (such as Florida). If this isn’t possible, consider putting an insect repellent on any exposed skin so that you don’t get bitten yourself while playing with your canine companion outside!
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Although heartworm disease can be fatal, it is also preventable. We hope that with the help of your veterinarian and this article you are able to prevent or treat heartworm disease in your dog.