September 13, 2020

What are the symptoms of heartworms in dogs

Heartworms are a serious disease that you don’t want your dog to be dealing with. But what are the symptoms of heartworms in dogs?

Your dog is your best friend. I can’t imagine not doing everything I can to keep my jack Russell, Maggie healthy. But as a new dog owner, you may not be sure what to look out for to ensure that your dog is healthy.


Heartworms are a serious disease that you don’t want your dog to be dealing with. But what are the symptoms of heartworms in dogs? This is a pertinent question to ask if you think there’s even the slightest chance your dog may be sick. Let’s take a look at some of the red flags to avoid, and also what they entail.


  • Laziness
  • Tiredness
  • Allergic reactions
  • Weight Loss
  • Coughing
  • Unusual shallow rapid breathing
  • Fainting spells

Symptoms explained

Your dog may begin to experience the symptoms explained above in different phases or stages.

Stage 1

At this stage, you may notice your dog has a cough that won’t go away, they may seem lazier than usual, and also they may start to lose appetite and consequently lose weight as well. The cough may seem like it’s brought on by the slightest things.

A cough that is caused by heartworms means that the worms are now affecting the lungs. The worms spread through the body causing the dog to lose energy and interest in what they usually enjoy, including eating.

Stage 2

As the heartworms progress through the body, they cause heavy breathing, resembling an asthma attack. You may then begin to see bulging ribs or stomach, which could be a sign of a fluid build-up

Stage 3

The final stage is what is most life-threatening. The heartworms can cause blood flow blockage which then can potentially lead to cardiovascular failure and give rise to a civil syndrome which can be seen by the exacerbated stage 1 symptoms compounded by sounds in the dog’s lungs and heart murmurs amongst other symptoms.

When should I get my dog tested?

If you begin to see symptoms that may lead you to think your dog has heartworms, you need to go to the vet. You can take preventative measures by vaccinating your puppy younger than six months.

After this, ensure that your dog gets his or her medication at least once a year. If you’ve just adopted a grown dog and not sure if he or she has received heartworm testing and medication, then you may want to get to the vet immediately, and then test again after six months.

Can heartworms in dogs be cured?

Yes, they can. Heartworm treatment is very specific and shouldn’t be winged. Once your dog has been diagnosed, it is advisable that you visit your veterinarian to get a step by step plan of treatment.

Relying on what you read and home diagnosis is not the most advisable. Always seek medical opinion for the good health and sanity of you and your dog.


The severity of heartworm symptoms can differ and do not always tally with treatment. It is advisable to hear what a veterinarian says.