Top Signs That Your Dog May Have Heartworms

Top Signs That Your Dog May Have Heartworms

Mosquitoes tend to increase their numbers when the weather gets wet and warm. These mosquitoes are more than just a nuisance as they are carriers and transmitters of heartworms in dogs. The parasite gets into the animal via a bite from a mosquito carrying the heartworm larvae. The infestation of these worms in your dog is a silent killer. This is because it can take months before your pet starts showing signs of infection. Here are the top signs that your dog has heartworms.



Fatigue is among the early signs that your dog has heartworms. You need to monitor your pet’s energy levels if you are suspicious. They may start showing intolerance to physical activities and may prefer to sleep most of the time. A clear sign of the infection is that they seem weaker and will be unwilling to participate in any activity, however simple it is.


Difficulty Breathing

As the heartworms spread into its lungs and bloodstream, your dog will have difficulty in breathing. This leads to the retention of fluids by the blood vessels in the lungs. This makes it hard for your dog’s body to synthesize oxygen, leading to rapid shallow breaths.



This is among the early symptoms that may typically start as a mild benign cough. A visit to the vet may only show that your dog is okay. It could mean that the infection is still in its infant stage and may not show in blood tests. Keep an eye on your dog, especially when they are exercising or playing. If the cough persists and gets worse, visit the vet immediately. This is because your pup may cough up blood or nosebleed as the infection progresses.


Bulging Chest

A bulging chest is a result of a build-up of fluid in your dog’s chest cavity. The chest cavity may also distend due to weight loss. Whatever the case, it is a sign of an adult heartworm infection. This is among the late-stage symptoms of heartworm disease, so you must visit your vet immediately.


Loss of Weight

As the disease progresses without treatment, some symptoms will get worse. One of these symptoms is appetite loss, which could have a heavy toll on your dog. It will affect your pet’s weight as they are unable to eat. If you notice that your dog has unusual weight loss, it may be in the late stages of heartworm infection. To be sure, take them to the vet to rule out any other possible illnesses.



Once a large population of heartworms enters your dog’s heart and bloodstream, they can completely block the flow of blood. This is the vena cava syndrome, which leads to shock making your dog faint or collapse. It is a result of the destruction of the red blood cells by the heavy influx of heartworms. In rare cases, the heartworms can make their way to your dog’s brain. This may cause blindness, seizures, and lameness.

These symptoms signify the latest stages of the disease. Your dog will die if you do not immediately consult your vet at this stage. Not all treatments are ideal since some will kill your dog in the event of a misdiagnosis.

To know more about the health of your dog, visit 4Paws Veterinary Hospital at our office in Duffield, Virginia. You can also call (276) 431-4838 to book an appointment today.

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Dr. Cortney Jessee