Caring for Your Heartworm-Positive Dog

Caring for Your Heartworm-Positive Dog

Credit: Zoetis, Dr. Claire Walther, DVM

Heartworm disease is a serious and potentially fatal condition caused by up to foot-long worms that live and cause damage within the heart, lungs, and blood vessels of unprotected mammals. Unfortunately, dogs are natural “hosts” for heartworm disease, leaving them highly susceptible to infection. This means it’s easy for heartworms to grow into adults, mate, and produce offspring, which can lead to a large infection and severe damage to the dog’s body and organs.

If left untreated, these heartworms can cause lung disease, heart failure, and serious damage to other organs of your dog’s body. The best way to prevent your dog from getting heartworm disease is to place them on a year-round heartworm preventative that guarantees protection for a full 12 months.

However, if your dog does test positive for heartworm disease (as many thousands of unprotected dogs do each year) there are treatment options available.

Treatment for heartworm positive dogs

Every dog and every case of heartworm disease is different. Your veterinarian will develop a treatment plan specifically for your heartworm positive dog and advise you on aftercare. There is more than one treatment approach for a heartworm positive dog, although injectable medication is the recommendation.


Only one medication (melarsomine dihydrochloride) is approved by the US Food and Drug Administration (FDA) for the treatment of heartworm disease in dogs. This is a reliable and safe treatment method that kills the heartworms living in your dog’s body. Along with this medication, your veterinarian may also prescribe a heartworm preventative, antibiotics, and steroids to help eradicate the heartworms and minimize complications arising from the death of these worms.

Special care during heartworm disease treatment

For up to 12 weeks after heartworm disease treatment (or until your dog tests negative for heartworm disease) the most important thing is keeping your heartworm positive dog calm and restricting exercise during this time. Successful heartworm disease treatment relies on temporarily avoiding any activity that could cause your dog’s blood pressure or heart rate to increase significantly. When a dog isn’t properly restricted from physical activity following treatment, dead heartworms can collect within vital organs and cause potentially fatal blood clots.

Tips to help your dog stay calm[3]:

  • Replace activity with affection. You can replace activity time with cuddles while you’re online, watching TV, or reading. Keep a leash or harness on your dog while cuddling, so they can’t bolt away when you’re not looking.
  • Keep them away from visitors. Both human and animal visitors can excite your dog. Keep your dog away from windows if they bark at people passing by.
  • Stay indoors. Keep your dog inside or in a kennel most of the time to restrict their activity. Kennel time doesn’t have to be a negative thing for your pup — take time to sit next to them and pet them with the kennel door open.
  • Keep them on a leash. When it’s time for a bathroom break, keep your dog on a leash to ensure that if they see something enticing (like a squirrel), they can’t take chase and their heart rate and blood pressure stays low. Avoid retractable leashes, as they offer far less reliable control and too much freedom.
  • Give them something to chew. A bored dog can be destructive. Durable chew toys give your dog a healthy and calm way to keep boredom away.
  • Stretch out meal times. Feed your dog with an interactive feeder or feed a portion of their daily food in a puzzle toy to help keep them entertained for hours while they try to get their food out.

Being treated for heartworm disease doesn’t give your dog immunity from getting infected again in the future. After heartworm disease treatment, it’s important to start your dog on a year-round heartworm disease preventative to protect them from having to endure the disease and its effects again. There are convenient injectable heartworm disease preventatives that last for 6 and 12 months, making it simple and easy to keep your dog protected from potentially fatal heartworm disease.

Note From Dr. Anderson: It is also important to note that while a year supply of heartworm prevention can seem a lot for your budget, the cost of treatment can range from $1,800 to $2000. Heartworm Prevention is a small price to pay to ensure your pet’s health. Companion Animal Hospital has several options available for prevention. Our hospital offers several rebates and some instant rebates that can be applied to your pet’s bill the day of purchase. Call and ask about the best option for your pet today! 931-359-6376