3 Heartworm Treatment Options for Your Dog

Dog laying down on rug

Did you know a positive heartworm test means your dog has adult heartworms that are 6–12 inches long?

The reason your pup is sickly and has lost his enthusiasm could be due to tens or hundreds of roundworms lodged in their body.

Heartworm disease is a chronic illness that takes 6–7 months to show symptoms. The heartworms live and multiply in your dog's system, interrupting blood supply to vital organs.

Your pet begins to show symptoms when the adult heartworms die of natural causes, and your dog’s immune system has a hard time breaking them down for reabsorption by their body.

Heartworm treatment options depend on the worm burden (ranging from 1–250 worms) and the immune strength of your pet. A strong immunity assists in faster recovery.

Giving your canine immune support supplements puts you ahead of the treatment process as you schedule to visit your veterinarian.

Your pet will undergo one of these treatment options — depending on the disease stage they are in:

  • Early-onset treatment
  • Advanced treatment 
  • Late-stage treatment

Let's dive in and discuss each treatment option in detail.

Treatment Options for Heartworm Disease

The heartworm treatment protocol your veterinarian will choose for your dog depends on the severity of the symptoms and the lab findings. Other considerations include:

  • Length of time your dog has had the infection 
  • How many heartworms are in your pup’s system
  • Your pet's overall body response to having the disease
  • Your dog’s activity level

The treatment process will take 3–8 months to kill adult heartworms, eradicate the microfilariae, and restore your pet’s overall well-being.

Option #1. Early Onset Heartworm Treatment

In this stage, the initial set of adult heartworms have matured, but they are at the early stage of causing organ damage. The new microfilariae larvae in the bloodstream are low in number to produce noticeable symptoms.

The adult worms target the heart and lungs first and can live there for up to 5 years.

Doggysupps heart support supplements strengthen your dog's heart muscles, which helps to fight off the disease.

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First Phase: The veterinarian will examine your dog and check if their body can withstand the heartworm disease treatment.

If the veterinarian is happy with the state of your pet, he’ll move to phase two. However, if there are concerns, he’ll change to the advanced stage treatment protocol.

Second Phase: The beginning of two deep intramuscular melarsomine injections given within 24 hours.

  1. Your dog will receive an oral sedative drug.
  2. The first Melarsomine injection is administered to kill adult heartworms.
  3. After an hour of observation, you’ll go home with pain medication and anti-inflammatory drugs.
  4. Your dog will be under strict exercise restrictions.

Third Phase: You’ll return the following day for the second round of medication.

  1. The veterinarian will examine your dog for signs of severe side effects such as progressive weakness, increased heart rate, and labored breathing.
  2. If all is well, a second injection is administered.
  3. You’ll continue with the pain medication and anti-inflammatory drugs.
  4. If there are no health complications, the follow-up visit will be 1–4 weeks later.
  5. You’ll start on monthly heartworm preventive medication at home.

Option #2. Advanced Stage Heartworm Treatment

At this point of diagnosis, the heartworms have lived in your pet’s heart, lungs, and major blood vessels for more than seven months and have caused significant organ damage.

The microfilariae circulate the bloodstream and mainly reside in the small blood vessels. The larvae block the blood flow in these vessels and deprive cells of nutrients and oxygen.

Your dog may show signs of liver disease like anemia, yellow eyes, and extreme weakness.

Heartworms in your dog's kidney cause the accumulation of toxins in their body with a change in urine color and little urine output.

With your pet going through these ailments, administering the injection to kill the adult heartworms in the first visit may be fatal to your dog. 

First phase: This stage lasts for 30 days or until your pup is strong enough to bear the melarsomine injections.

  1. Your veterinarian will stabilize your dog by giving them anti-inflammatory drugs and antibiotics.
  2. The veterinarian may prescribe immune supplements to boost your animal’s fighting chances.
  3. Your pet will start taking heartworm prevention medications.
  4. You’ll enforce exercise restrictions with most times spent indoors.

Second Phase: This stage comes 30 days after the first phase. Your veterinarian will perform blood tests to check the heart, liver, and kidney function.

  1. The first melarsomine injection is administered.
  2. Your dog will receive the monthly heartworm preventatives.
  3. Your pet may spend a night or two in the hospital.
  4. Your dog will receive pain medication and continue with the anti-inflammatory drugs. 
  5. You’ll continue with exercise restrictions and more cage time.

Third Phase: This phase comes 30 days after the second phase treatment process. Your veterinarian will administer two injections within 24 hours.

  1. Your dog will receive the second injection.
  2. Your veterinarian will give your pet the monthly heartworm prevention medication.
  3. You’ll return the following day for a third dose.
  4. Activity and exercise restriction continues for 6–8 weeks
  5. Your vet will schedule monthly follow-up visits.

We then recommended immune supplements until full recovery.

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Option #3. Late Stage Heartworm Treatment

The worm load at this stage overwhelms your dog's body, and they can barely function. Surgically removing the heartworms is the only treatment option to save your pet’s life.

The large heartworm numbers will limit the effect of melarsomine injections in eliminating all the adult heartworms in good time to save your dog.

The surgery aims at removing the worms in the heart (right atrium) through an incision in the right jugular vein.

The injections and oral preventive medication will eradicate the remaining adult worms and microfilariae larvae.

First Phase: Usually an emergency surgical procedure.

  1. Your veterinarian will stabilize the dog with antibiotics and anti-inflammatory.
  2. The surgical procedure will be performed.
  3. Your pet will be admitted until they are strong enough for home care.

Second Phase: Your pet will receive the same treatment protocol as the advanced stage. The first dose of melarsomine injection is administered, and heartworm prevention medication is started.

Third phase: The second and third injections are administered with complete restriction of activities. Close follow-up visits are scheduled with monthly heartworm preventives strictly given.

Which Stage of the Heartworm Disease Is Your Pet In?

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Heartworm disease caused by Dirofilaria Immitis enters your dog's bloodstream from a mosquito bite. The Microfilariae larvae deposits take 6–7 months to mature.

The adult worms mate to produce more microfilariae that a heartworm antigen blood test can detect.

A routine test done at this asymptomatic stage can prevent further disease progression by administering treatment. The medication would kill the few adult heartworms present and eliminate the microfilariae — ending the life cycle.

If treatment delays, the heartworms continue to multiply until the symptoms appear.

The most severe heartworm cases occur when the adult worms live in multiple organs, and all the major blood vessels are compromised, causing insufficient blood supply to the cells.

Let’s elaborate on the stages in the table below.

Stage of Heartworm Disease Symptoms Lab Test Findings
Early-onset stage (Class 1 and 2)

- No symptoms

- Occasional cough

- Mild tiredness after activity

- Positive antigen test for adult heartworms

- Chest x rays show little to no changes

- Blood cell count shows slight changes

Advanced Stage (Class 3)

- Persistent cough

- Dog is dull and inactive

- Exercise intolerance

- Labored breathing

- Signs of heart failure and lung disease

- Positive heartworm antigen test

- Significant changes in the chest x rays

- Blood cell count shows marked changes due to organ damage

Late-stage (Class 4)

- Caval Syndrome

- Heart failure due to blockage by heartworms

- Severe lung disease

- Weight loss

- Complete inactivity

- Positive antigen test for adult heartworms

- Life-threatening changes in the scans

- Blood work and serum biochemistry show full organ damage

Allow Doggysupps Natural Supplements to Strengthen Your Dog’s Heart and Immune System

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Heartworm disease snatches the joy you get from your dog’s enthusiastic attitude and warm hugs. The treatment process takes months and leaves you wishing for the good old fun days.

Doggysupps understands that prevention is better than cure. Our natural supplements are a great addition to the monthly heartworm prevention medication. Our supplements boost your dog’s immunity and strengthen their heart muscles.

When a disease like heartworm strikes, your pup’s chances of survival manifold.

Place your order today and take your dog to a higher, healthier level.



Featured Image: Unsplash by Mike Burke

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