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Heartworm Disease in Dogs: Prevention & Treatment

There is a serious condition that dogs can develop called Heartworm disease. This disease can cause irreparable damage to your dog's organs. In this blog, our Scottsdale vets discuss the importance of heartworm prevention and how it can be treated.

What Is heartworm disease?

When your dog is bitten by an infected mosquito, a parasitic worm called Dirofilaria immitis enters their bloodstream and causes heartworm disease. Heartworm is not contagious and cannot be transmitted from one infected dog to another; it is spread only by mosquitos that carry the parasite. Don't think your dog's risk of heartworm is low; there have been reports of heartworm in all 50 states, and it is especially common between New Jersey and the Gulf of Mexico, including along the Mississippi River and its major tributaries.

If your pup has been bitten by an infected mosquito, the worms will grow into adults, mate, and produce offspring while residing in your companion's heart, lungs, and blood vessels.

Heartworm Prevention For Dogs

Our veterinarians at Scottsdale Ranch Animal Hospital cannot emphasize enough the importance of heartworm prevention, which is far superior to the treatment involved. If you have not already established a prevention plan for your dog, we recommend that you do so as soon as possible.

Usually, heartworm prevention is administered through a monthly medication that is prescribed by your vet. 

Treating Heartworm In Dogs

In situations where preventative measures don't work in preventing infection, there are treatment options available for your dog, however, all have potential side effects that can be serious and can cause health complications, however, fatalities are rare.

Since heartworm is undetectable until at least 5 months after infection, many dogs already have advanced Heartworm Disease by the time they are diagnosed and require fast and intense treatment. In rare situations, the damage to the dog's internal organs can be so severe that by the time the condition is found it's better to treat the damage and keep the pooch comfortable rather than taking the additional risks associated with attempting to kill the heartworms. Dogs in this advanced condition have a life expectancy of only a few weeks or months. 

If you see your dog displaying any of the signs of heartworm disease contact your vet immediately. Some of the symptoms of heartworm include fatigue, getting tired easily after only mild exercise, a persistent cough, a large belly, reduced appetite, and weight loss. There are some rare and very severe situations where dogs can get Caval Syndrome where your pup could suddenly collapse and potentially die.

Fortunately, a new medication has been developed to kill adult heartworms while causing fewer harmful side effects. Melarsomine is an injectable drug that kills adult heartworms and is given in multiple injections. Typically, your dog will be given a 30-day rest period following their first injection, followed by two additional injections 24 hours apart. Antibiotics will also be prescribed to treat any infectious bacteria that the heartworms may carry. With this new medication, 95% of dogs with heartworms can now be effectively treated.

Your dog will also receive treatment to kill juvenile heartworms (microfilaria) either before or after their Melarsomine treatment. Your dog may need to spend the night in the hospital for observation on the day this treatment is administered.

What To Do After Your Dog Has Been Treated For Heartworms

Your dog must be allowed to rest after the injection. Heartworm treatment in dogs kills adult heartworms within a few days, but complications can arise while their bodies decompose. It may take several months for the heartworms to be reabsorbed into the patient's blood. Most post-treatment complications are caused by decomposing heartworm fragments, so to reduce this risk, your dog should not be allowed to exercise and should be kept as quiet as possible for the first month after treatment. The cough will be noticeable for seven to eight weeks after the injection. If your dog's cough persists or becomes particularly severe, or if he experiences shortness of breath or fever, contact your veterinarian immediately.

The Side Effects Of Heartworm Treatment In Dogs

Heartworm treatment can have serious consequences for your pet's health and is potentially toxic to the dog's body. Many dogs experience soreness and swelling where they have received injections. The most severe side effects are caused by a large number of worms suddenly dying. If your dog is panting excessively, having difficulty breathing, becoming lethargic or collapsing, rejecting their food, vomiting, or developing diarrhea, you must contact your veterinarian immediately.

Contact our vets at Scottsdale Ranch Animal Hospital immediately if they are displaying any signs of heartworm or side effects of their heartworm treatment. 

Get in touch today to book your pet's first appointment.

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