Heartworm in Pets: Everything You Need to Know According to Experts

As a dog or cat owner, you want to do everything to keep your furry friend healthy and safe. In addition to cat and dog vaccinations, routine check-ups, and a healthy diet, you also need to be aware of the dangers of heartworm.

Heartworm is a parasitic infection that can be deadly to dogs, cats, and ferrets. Here’s what you should know about heartworm in pets, including the signs and symptoms, treatment options, and recovery process.

What Is Heartworm?

According to the experts, heartworm is a parasitic infection transmitted to dogs, cats, and ferrets by mosquitoes. The infection occurs when a mosquito bites an infected animal and then feeds on the blood of a healthy animal.

After the mosquito takes a blood meal, it also injects microfilariae (heartworm larvae) into the animal’s bloodstream. These larvae mature for several months (6-7 months) and eventually grow into adult heartworms.

Adult heartworms can grow up to 12 inches long and live on the right side of the heart and nearby pulmonary arteries. The worms can cause serious health problems for animals, including heart failure and damage to other organs.

What Are the Signs and Symptoms of Heartworm Disease?

The signs and symptoms of heartworm disease can vary depending on the stage of the disease.

In the early period, you may not notice signs or symptoms at all. As the disease progresses, animals may start to show the following:

  • Fatigue
  • Cough
  • Difficulty breathing
  • Weight loss
  • Lethargy

In the later stages of the disease, heart failure can occur, requiring cat or dog urgent veterinary care. Animals with heart failure may collapse, have an irregular heartbeat, and fluid may build up in their abdomen.

Diagnosis of Heartworm Disease in Pets

If you believe that your pet may have heartworm disease, the first step is to take them to the vet. Your vet will perform a physical test and ask about your pet’s symptoms and medical history.

They may also require one or more of the following tests:

  • Blood test: A blood test can be used to detect the presence of adult heartworms in an animal’s bloodstream.
  • X-rays: X-rays can be used to look for heartworms in the lungs and heart.
  • Echocardiogram (heart ultrasound): This test can be used to assess heart function and look for signs of heartworm damage.
  • Ultrasound: This imaging test can show worms in the heart or lungs.

Treatment for Heartworm Disease in Pets

After your pet is diagnosed with heartworm disease, treatment will be necessary to kill the worms and prevent further damage to the lungs and heart. Treatment for heartworm disease typically involves a combination of drugs. But the exact treatment depends on the severity of the infection and your pet’s health.

Treatment options include:

1. Heartworm Preventive Medication

This medication kills heartworm larvae before they can mature into adults. It is given monthly and is available by prescription from your vet.

2. Adulticide Therapy

This treatment kills adult heartworms and is typically given as injections for several weeks.

3. Corticosteroids

These drugs are used to help reduce inflammation caused by heartworms. They may be given orally or injected.

4. Antibiotics

These drugs are used to treat secondary bacterial infections due to heartworm disease.

5. Hospitalization

In some cases, animals with heartworm disease may need to be hospitalized for treatment. This is often only necessary in severe cases where the animal has difficulty breathing or is in heart failure.

Recovery from Heartworm Disease

The good news is that many animals with heartworm disease recover with treatment and live happy, healthy lives. The recovery process can take several weeks to months, and you must follow your vet’s instructions. Here are additional tips to help them through this process:

  • Provide plenty of rest: Animals with heartworm disease need plenty of rest to allow their body to heal. This means keeping them indoors and limiting their activity.
  • Offer a nutritious diet: A healthy diet will help your pet’s body recover from the infection. Ask your veterinarian about the best type of food for your pet.
  • Give medications as prescribed: Be sure to give your pet any medications prescribed by the vet, such as heartworm preventative medication, antibiotics, or corticosteroids.
  • Monitor for signs of improvement: As your pet feels better, they may have more energy and be more active. Watch for these signs and let your vet know if you see any changes.

How to Prevent Heartworm in Pets

The best heartworm prevention for your pet is to give them monthly heartworm preventive medication. This medication kills heartworm larvae before they can mature into adults.

There are various heartworm preventives available, so talk to your veterinarian about which one is right for your pet.

In addition to giving your pet preventive medication, you should also take steps to protect them from mosquitoes. These insects can transmit heartworm larvae to animals, so you should keep them away from your pet as much as possible. Here are some tips:

  • Keep them indoors: If possible, keep your pet indoors during peak mosquito hours, typically dawn and dusk.
  • Use mosquito repellent: Apply mosquito repellent to your pet’s skin or fur before going outside. You can also use mosquito coils or other devices to help keep mosquitoes away from them.
  • Cover their skin: When outdoors, dress your pet in long-sleeves and pants to help keep mosquitoes off their skin.
  • Keep their area clean: Remove standing water from your property, as this is where mosquitoes lay their eggs. This includes filling in any holes or puddles and emptying any outdoor containers that may hold water.


Heartworm is a serious disease that can also be deadly to pets. It is caused by parasites that are transmitted by mosquitoes, and it can affect dogs, cats, and other animals.

The key to protecting your pets from having this disease is to be aware of the symptoms, get them tested and vaccinated regularly, and use monthly preventive medication. Always choose a full-service pet hospital that offers complete facilities, vet services, and lab testing.