Cart --
0 Items in Cart
Your Shopping Cart is Empty
TOGGLE

Heartworm Symptoms - The Four Stages of Heartworm in Dogs

Does Your Dog Have Heartworm? Track the 4 Stages of Heartworm Symptoms

By April 25, 2012 | See Comments

  • expert or vet photo
    vet verified

    PetCareRx Staff Veterinarian

    DVM

Dog with heartworm symptoms

Heartworm symptoms can be subtle and tricky to detect. Learn more about heartworm symptoms here.

 

While potentially fatal if untreated, heartworm symptoms can be initially quite mild. Early in the disease’s progression, there may not be any symptoms present at all, which is part of what makes heartworm such a difficult disease to diagnose. It is because of these reasons that monthly treatment with a preventative, like Heartgard for dogs, Iverhart Max, or Trifexis is so important.

As with cancer, heartworm disease is divided up into four stages. The mild cough of stage one or two progresses into a persistent cough by stages three and four. Without treatment, the symptoms become increasingly disruptive and severe, and the impact on a dog’s lungs and heart is negative. Your dog’s stage of heartworm disease – as well as other considerations like age and health – will play a major role in determining your veterinarian’s approach to treatment.

The primary observable heartworm symptoms are a cough that just won’t seem to go away, difficulties breathing, being tired after exercise, and at a certain point, a reluctance to exercise at all. Below, see how symptoms match to each of the progressively more entrenched stages of the disease.

Stage 1

During the first stage of heartworm disease, dogs generally will not have any symptoms at all, although you may notice a slight cough. This is a very mild stage, and dogs will appear happy and healthy. Even with a physical, this disease is difficult to detect, and blood tests may come back with a negative result for heartworm disease.

Stage 2

Stage two of heartworm disease is accompanied by moderate symptoms such as a lingering cough or fatigue after exercise. The symptoms may now be advanced enough for you to detect them. During this phase, the impact of the heartworms on a dog may show in tests.

Stage 3

By stage three, the disease is having a real impact on your dog’s health, and the heartworm symptoms are correspondingly more severe and noticeable. Dogs will continue to cough, will experience fatigue after exercise, may be reluctant to exercise, and can have trouble breathing. During this stage, dogs may also cough up blood. By stage three, the disease is quite evident on x-rays.

Stage 4

Dogs in stage four of the disease have very visible heartworm symptoms, which are accompanied by long-term implications for the dog’s health. As in other stages, dogs will be reluctant to exercise, tired after exercising, and will exhibit a cough. Dogs will probably experience trouble breathing as well. Testing may reveal the impact of the disease in the form of abnormal lung sounds within the dog’s lungs, an enlarged liver, and heart noises. Untreated, this stage of heartworm disease can lead to death.

At each stage of the disease, treatment methods become increasingly more severe and invasive. Be mindful of your dog’s typical behavior, so that potential symptoms like a reluctance to exercise or extended lethargy don't get overlooked. Taking heartworm medication has a good success rate at keeping larval infections from maturing into adult heartworms, especially when augmented by annual heartworm tests to detect signs of the disease.

How PetPlus Can Help

If your dog is taking heartworm medication, or anything else, PetPlus can help make buying their medications much more affordable. With discounts on brand name heartworm medications like Heartgard, Tri-Heart, and Iverhart Max as high as 47% off, PetPlus can save pet parents a considerable amount of money.

This information is for informational purposes only and is not meant as a substitute for the professional advice of, or diagnosis or treatment by,your veterinarian with respect to your pet. It has, however, been verified by a licensed veterinarian for accuracy.

2016-02-26T21:16:20

Hi everyone. I'm sorry to hear your Heartworm stories. :( I am the owner of a once neglected/dumped dog who tested positive for heartworms when we took her in for initial workup/spay, etc. She is an active hound mix, and I knew she would not tolerate the treatment, so we did not treat.

However, I did give her a 16-oz. Wormwood and Black Walnut tincture (maybe Native Essence?) about 1 tsp. or so in her food every day until it was gone. That's all I ever did to treat her. She is an outside dog, and she is now 11 years old with almost no symptoms. I've heard her cough maybe 5 times in her life.

I cannot claim that she is cured, because she has never gone back to the vet (I thought she's been dying for 11 years). Perhaps the test was a false positive. And I understand that all dogs and their infestations are different. I just wanted to share my story. I wish you, and your animals friends, the best.


2016-02-22T07:26:48

Kim... (((OR ANYONE WHO THINKS THEY KNOW enough about this ))).my dog is about 13 years old and has heart worms...i have some questions...i think she is dying but im desperate and grasping at straws. Can you please email me if you are willing to hear me out and give me an opinion based on your experience so far, please email me asap SheanaRei@gmail.com thank you


2015-12-22T05:41:56

My dog, that is now 13 years old, was diagnosed with heartworms 5 years ago. We let nature take it's course, but he never did let the heartworms get him. Its a personal decision between you and your family, but I don't necessarily thinks its a death sentence. I know my dog has lived a happy life just taking preventive heartworm care to keep it from getting worse.

comments powered by Disqus

Was this article helpful?