Why adopt a Heartworm Positive Dog?

Heartworm Adoption Programs

Adopting a heartworm positive dog is not for all adopters.  When you decide to adopt a heartworm positive dog you are leaving the world of dog ownership and entering the world of animal rescue. 

Texas alone euthanizes 125,000 dogs per year and roughly 50% of dogs over 2 years of age that we rescue in the rural south are heartworm positive. Overcrowded shelters have to decide which animals to put down daily.  Due to the low adoption rates, cost of treatment and length of treatment time, heartworm positive dogs are the first to be euthanized.

Let Love Live believes that every animal should have the chance to find a loving home regardless of breed or medical condition and for that reason we are one of the few rescues that will take heartworm positive dogs. Many rescues only “rescue” the most adoptable dogs and avoid the hardship cases. Not us!  When you choose to adopt a heartworm positive dog you are saving a life that otherwise would have been destroyed. You are truly rescuing the most at risk animals.  You are not just an adopter, you are a rescuer!

This handbook explains all the aspects of heartworm disease, treatment options and what you as an adopter can expect in terms of success with your rescue pet. It also explains the two different programs we offer when adopting a heartworm positive dog and the support we will give you and your rescue animal to ensure the most successful outcome possible. 

Rescuing a heartworm positive dog is not for all adopters but for those who do, it is an exceptionally rewarding experience knowing you stepped up to save a life that others passed by and were willing to let perish.

Let Love Live offers two programs when adopting a heartworm positive dog:

Treat-To-Adopt – Adoption Fee $300 for Altered/$210 Unaltered

If you choose to “Treat-To-Adopt” you will take the dog home with you as if you are adopting the pet.  However, we provide medications needed to treat your pet under the “Moxi-Doxy” (see more below)  to treat your pet’s heartworm.  At 12 months, if the animal’s heartworm test comes back negative, our medical commitment ends. 

If at 12 months after treatment start date the animal still tests positive for heartworm, we will pay for a second round of “Moxi-Doxy” treatment.  If the pet fails the second round of treatment we will discuss with you options going forward at that point.

Throughout the process we are available for any help or support you may need while your pet undergoes treatment.  You may return the animal for a full refund of your adoption fee at any time before the pet tests heartworm negative. Once the pet tests negative our normal adoption policies will apply and there will be no refund of adoption fees if you return the pet. 

Adopt-To-Rescue – Adoption Fee $125 Altered/$75 Unaltered

If you choose to “Adopt-To-Rescue” then you adopt the animal immediately as if you were doing a normal adoption.  You will take on all responsibility for the animal’s care, medical and otherwise.  It will be between you and your personal veterinarian how to proceed with heartworm treatment and what treatment protocol to follow.  

If you choose this option we offer a discounted adoption fee of $125 to help offset your future medical costs.  

By choosing to “Adopt-To-Rescue” you are stepping up as part of our animal rescue team and you are freeing up Let Love Live’s resources so we can rescue more animals.  

When you “Adopt-To-Rescue” you can take pride that you not only rescue the animal that you adopt but you also help us free up resources to rescue another heartworm animal that would potentially be euthanized if not for your love and support!!

The Basics of Heartworm

This is a quick overview of heartworm (for more detailed information please go to www.heartwormsociety.org.

Heartworms are parasites that live in the heart, lungs and blood vessels of infected dogs. The worms can grow up to a foot long.  They can do severe damage to the cardiovascular system causing fatigue, exercise intolerance and coughing up blood.  If not treated the heartworms will eventually lead to an early death. 

This is a chart of the lifecycle and routes of infection.  Note that a dog can not get heartworm directly from another dog and only through a mosquito that bites a dog that has microfilaria (larvae) present and then bites an uninfected dog.

This chart demonstrates the lifecycle and routes of infection of heartworm disease.  Note that a dog can not get heartworm directly from another dog and only through a mosquito that bites a dog that has microfilaria present.

Prevention and Treatment Options

Heartworm preventives kill worms that are 2 months old or younger.  If a preventative is not given consistently these young worms will develop into adult worms which then requires further treatment. 

There are 2 treatment protocols for Heartworm disease, the so called “fast-kill” and so called “slow kill” methods.  Both treatments utilize the antibiotic doxycycline to kill the bacteria wolbachia with which heartworms have a symbiotic relationship.  Without the wolbachia the adult worms begin to die.  However microfilaria (larvae) will persist in the dogs bloodstream until all female worms are completely killed. 

Note: Worms that are 3-5 months or older are not affected by heartworm preventatives.  Worms 3-5 months old are also not killed by Immiticide used in “fast-kill” protocols.  However these 3-5 month old worms are killed when doxycycline is added to the protocol.
Here is a link with excellent information on both treatment types and research studies that have been done: http://dogaware.com/health/heartworm.html


This method consists of a 30 day treatment of doxycycline followed by 1 injection and then 2 injections 30 days later of Immiticide (melarsomine) to kill the adult worms.  Because this method kills the worms quickly after the injections, it is recommended that the animal be on strict kennel quarantine for 30 days as any exertion can cause the dead worms to cause an adverse pulmonary event.  Because it takes time for the dog’s immune system to break down the dead worms, it can take up to 10 months before a negative heartworm test can be achieved even though the worms have been killed.


Worms are killed quickly eliminating further cardiovascular damage. A near 100% effective rate at killing adult worms.


A high cost from $600-$1200.

Strict kennel quarantine for 30 days requiring that the dog stay in a kennel and avoid all activity other than short walks for bathroom breaks.


Also known as “moxi-doxy”, this method is relatively new with effectiveness studies only done in the past few years.  This protocol consists of 30 days of doxycycline to kill the wolbachia bacteria and a once yearly administration heartworm preventative Proheart 12 (moxidectin).   Once the wolbachia have been killed, the worms begin to die while the Proheart 12 kills off any microfilaria (larvae).  This process to kill the worms takes place over time thus reducing the need for strict kennel quarantine for 30 days.  High impact exercise needs to be avoided.  However, light exertion on leash and light running and play is acceptable until a negative heartworm test is achieved 12 months later.  


A low cost alternative.  The only added cost is the extra cost of the Proheart 12 vs. other Heartworm preventatives.  Strict kennel confinement is not necessary.  


A slightly lower success rate than Immiticide.  Studies have shown that 96% of all worms are eliminated at 10 months with half of all animals having all worms eliminated.  There is a slight possibility that a dog will antigen test negative even though 1 or 2 worms may still be present.  There is also a possibility of a second round of doxycycline being needed 1 year after the initial treatment

A possibility for further cardiovascular damage over the several months needed to kill the worms.

Both of these protocols, even when 100% effective at killing the heartworms immediately (with “fast-kill”) or over a few months (with “slow-kill”), will still not result in a negative heartworm test for up to 10 months after treatment.  However a microfilaria test can be conducted which will show whether female heartworms are still present. 

Due to the high cost of immiticide treatment, Let Love Live has chosen that our “Treat-To-Adopt” program will treat heartworm positive dogs with the “moxi-doxy” protocol. We will do Immiticide if we are able to secure a sponsor or funding for a specific dog to undergo treatment.  If you “Adopt-To-Rescue” you are free to choose either treatment protocol with the veterinarian of your choice.


Please note the following when considering adopting a Heartworm positive dog:

  1. Strict adherence to medical treatment is extremely important to guarantee the most positive outcome possible.  Your adopted pet will need to be on monthly heartworm preventative year round for the rest of their lives.
  2. Heartworm positive animals may have permanent and irreversible damage related to their infection.  The amount and extensiveness varies by animal and severity of infection.  Any vet expenses relating to this are the sole responsibility of the adopter. 
  3. Successful treatment is not guaranteed as there are rare cases of treatment resistant heartworm disease.  The animal you adopt may never test negative and have to live with heartworms until the heartworms die naturally after several years.  
  4. Regardless of which treatment option is pursued, there is the very small yet real possibility that the pet you adopt may not survive treatment.
  5. Because the animal you are bringing home has heartworm disease and may have microfilaria present during treatment, it is very important that all animals in your household be on heartworm preventatives even outside of mosquito season.
  6. Following exercise guidelines for the duration of treatment outlined in our “Heartworm Adoption Handbook” is extremely important for the safety and wellbeing of the heartworm positive animal.

Let Love Live

Yes, there are extra costs.  Yes, there are risks.  However, the rewards of saving the life of an amazing animal and the joy of Letting Love Live are incalculable!

Welcome to the Let Love Live team!  Welcome to the world of rescue!!

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