What is Heart Worm and How Do Dogs Get It?

One of the deadliest and most common of all worm infections in dogs is heart worm (heartworm). If left untreated, heartworm can quickly turn into a fatal condition for even healthy dogs of all ages, as well as more than 30 different species of animals such as cats, wolves, coyotes, ferrets, and even sea lions. And believe it or not, heart worm can affect humans as well.

Fortunately, heartworm is considered 100% preventable, if you are well informed about the condition and the many different preventatives available. Heartworm preventatives are readily available in the form of both prescription and non-prescription medicine and pills.


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Heartworm medicine can be purchased without a prescription through a number of reputable online sources, but one of the most popular online sources is “Heartworm Medicine.” Heartworm Medicine – www.heartworm-medicine.info – is a website that sells a wide selection of non-prescription heart worm medicine. The site offers the lowest prices on the Internet for top heart worm medicine brand names such as Heartgard, Nuhart, and Advantage. Heartworm-medicine.info also features easy to understand information about heart worm, as well as detailed safety, dosage, and side effect information for all of its products.

Before we discuss the different types of prescription and non-prescription heart worm preventatives available, please continue reading to find out more about heart worm in dogs and how to recognize it.

About Heartworm

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Heartworm cases have been reported all over the United States, in breeds of all kinds, and in younger and older dogs. Heartworm does not discriminate when it comes to gender either. Dogs of all kinds can become infected with heart worm through insect bites, particularly mosquito bites. When a mosquito bites a dog, the infection is transmitted through the dog’s skin. The larvae develop in the body over a period of several months during which time they grow and migrate to the heart, lungs, and blood vessels.

Symptoms of heart worm in dogs include:

  • Abnormal heart sounds
  • Abnormal lung sounds
  • Difficulty breathing
  • Enlargement of the liver
  • Exercise intolerance
  • Fluid accumulation in the abdomen
  • Temporary loss of consciousness

In the earliest stages of heart worm, there are no abnormal signs of infection. In mild cases, coughing is present. In the moderate stage, you may notice coughing, exercise intolerance, and abnormal lung sounds. In the most severe cases, all of the above symptoms may be present. If the infection is severe enough, it will result in death.

Heartworm Treatment and Preventatives

There are many conventional treatments for heart worm that are considered highly effective. There are also many natural treatments for canine heart worm that may be effective in the early stages of the condition. The goal for conventional treatments for canine heart worm is to kill all adult worms with an adulticide and all microfilariae with a microfilaricide. The American Heartworm Society offers the detailed treatment description below. Please read carefully.

Adult Heartworm Therapy (Adulticide Therapy)
There is currently one drug approved by the FDA for use in dogs for the elimination of adult heart worms. This drug is an organic arsenical compound. Dogs receiving this drug therapy will typically have had a thorough pretreatment evaluation of its condition and will then be hospitalized during the administration of the drug. Melarsomine dihydrochloride (Immiticide, Merial) has demonstrated a higher level of effectiveness and safety than any other adult heart worm treatment previously available. It is administered by deep intramuscular injection into the lumbar muscles. For complete information on the classification and treatment for heart worm infected dogs using this product, consult your veterinarian.

Post-Adulticide Complications
The primary post-adulticide complication is the development of severe pulmonary thromboembolism. Pulmonary thromboembolism results from the obstruction of blood flow through pulmonary arteries due to the presence of dead heart worms and lesions in the arteries and capillaries of the lungs. If heart worm adulticide treatment is effective, some degree of pulmonary thromboembolism will occur.

When dead worms are numerous and arterial injury is severe, widespread obstruction of arteries can occur. Clinical signs most commonly observed include fever, cough, hemoptysis (blood in the sputum) and potentially sudden death. It is extremely important to not allow exercise in any dog being treated for heart worms. Often dogs with severe infections will also require the administration of anti-inflammatory doses of corticosteroids.

Elimination of Microfilariae
The most effective drugs for this purpose are the macrocyclic lactone (ML) anthelmintics, i.e.,milbemycin oxime, selamectin, moxidectin and ivermectin. These drugs are the active ingredients in commonly used heart worm preventives. Although usage as microfilaricides has not been approved by the FDA, they are widely used by veterinarians as there are no approved microfilaricidal drugs currently available. It is recommended that microfilariae positive dogs being treated with these macrocyclic lactones be hospitalized for at least eight hours following treatment for observation of possible adverse reactions, including those resulting from rapid death of the microfilariae.

Circulating microfilariae usually can be eliminated within a few weeks by the administration of the ML-type drugs mentioned above. Today however, the most widely used microfilaricidal treatment is to simply administer ML preventives as usual, and the microfilariae will be cleared slowly over a period of about six to nine months. – The American Heartworm Society

While treatment for canine heart worm is best administered under a vets care, some dogs may be too old or too sick to undergo rigorous treatments. They may be too old for strong preventative prescription medications as well. This is where non-prescription preventative medicines can be highly effective.

Non-prescription preventative care in the form of monthly tablets, chewables, or topicals includes: Ivermectin, Macrocyclic Lactone (ML), Milbemycin, Moxidectin, and Selamectin. Natural cures for canine heart worms are not regulated, so you will find literally hundreds, if not thousands, of products on the market that claim to cure or prevent canine heart worm.

If you are interested in alternative cures for heart worm, it’s best to speak with your vet or contact the American Holistic Veterinary Medical Association to locate a holistic vet in your area.

American Holistic Veterinary Medical Association
2218 Old Emmorton Road
Bel Air, MD 21015
phone 410-569-0795
fax 410-569-2346
e-mail: [email protected]
website: http://www.ahvma.org/

Author: The Top Worm

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