What’s the big deal about heartworms?

If you’ve taken your dog to the vet, you’ve likely heard talk about getting them on heartworm prevention. Maybe it sounds like just one more thing to add to the to-do list, or you’ve wondered how serious it really is. But the reality is, heartworm disease is very serious and a common infection that has been found worldwide in millions of pets.

To protect dogs from the fatal disease it is important that they get tested regularly, stay on prevention year-round, and receive prompt treatment if they do test positive.

What are heartworms? How do dogs get them? ^[1]

Heartworm disease is spread when your dog gets bit by a mosquito carrying the larvae of a parasite called Dirofilaria immitis (heartworm). The bite spreads the larva to your dog, where they grow into long, slender creatures that are known as adult heartworms. They can grow to be 6-12 inches long (keep scrolling if you’re curious to see what they look like).

Adult heartworms live in blood vessels in a dog’s lungs and heart, where they cause severe damage and death if left untreated. At about 6 months old when they are fully mature, heartworms begin to reproduce and infect your pet’s bloodstream even more.

Did you know that dogs can pass on heartworms to mosquitoes as well? If a mosquito bites a heartworm-positive dog, it can catch the disease and spread it to other pets, continuing the damaging cycle of heartworm disease.

What are the first signs? ^[2]

There are often no physical symptoms of heartworm disease until a dog has had it for a while. Once they do begin showing symptoms, these can include:

Persistent coughing
Tiredness after moderate activity
Decreased desire to exercise
Lower appetite
Difficulty breathing

At more advanced stages, dogs may have dark urine or pale gums. At this point they have likely developed caval syndrome, when blood flow within the heart is being blocked. This is a severe form of the disease that usually requires immediate surgical removal of heartworms to prevent heart failure from occurring.

Does my dog really need heartworm prevention?

To protect dogs from getting heartworm disease, they should be regularly tested for heartworms and stay on prevention year-round.

Heartworm disease, treatment, and recovery is far worse and more expensive than keeping your dog on prevention. The cost for heartworm prevention can be as little as $35 for 6 months. Heartworm treatment, however, can cost hundreds to even thousands of dollars. Besides this, treatment will not prevent your dog from getting heartworms in the future.

In addition to being costly, treatment requires multiple visits to the vet, close observation of your dog, and limiting of physical activity during the entire process. Trying to keep a dog from playing for months at a time is not fun for anyone involved.

But what if my pet stays indoors?

Unfortunately, mosquitoes don’t ask permission to walk through the front door. It only takes one bite from an infected mosquito to transmit heartworms to your pet. Whether your pet is mostly outdoors, only goes out to use the restroom, or stays indoors, we recommend giving them heartworm prevention year-round. This can prevent that one mosquito bite from transmitting the fatal heartworm disease to them.

Does my dog have to be tested before getting prevention?

Dogs are required to be tested for heartworms before starting on prevention. This is because heartworm prevention kills immature heartworms, not adult ones. If a dog was put on prevention without being tested, any adult heartworms they had would continue causing damage. Heartworm testing lets us know if any adult heartworms are living in your dog, in which case they need heartworm treatment with close monitoring.

At Low Cost Pet Vax, we offer heartworm testing at all of our mobile clinics for $27. Click here to see where we’ll be located this weekend.

What if my dog tests positive?

If your dog has tested positive for heartworms, the next step is to set up an appointment at the vet and get started on a treatment plan. At Low Cost Pet Vet in Irving and San Antonio, we offer $34 heartworm treatment consultations to discuss options with a veterinarian and receive an estimate for treatment. Treatment at our clinics generally costs $400-$800 and takes 7-8 months.

While your vet may recommend additional services based on your dog’s needs, a general heartworm treatment plan involves the following:

Before treatment begins, your dog is given heartworm prevention and an antibiotic (doxycycline) to kill off baby heartworms and weaken the adult heartworms. Your dog will be closely monitored for potential reactions.

After 30 days, your dog will be given its first heartworm treatment injection with the drug melarsomine. After each injection and throughout treatment, it is extremely important that dogs are closely monitored and prevented from being physically active.

30 days later, the second dose of melarsomine will be administered.

The next day, the third and final dose of melarsomine will be administered.

9 months later, heartworm testing is recommended to make sure all adult heartworms have been killed.

After treatment, dogs should continue to take heartworm prevention for the rest of their life.

Heartworm prevention:

There are a few different options available for heartworm prevention. Some popular alternatives are:

ProHeart 6 and ProHeart 12: These are extremely convenient injections that last 6 and 12 months, respectively. By choosing an injectable prevention, there’s no need to remember to give a monthly pill. Instead, you can take care of it during the annual vet visit and leave with the peace of mind that your dog is protected for the next 6 months or year.

At Low Cost Pet Vax, the cost for ProHeart 6 ranges from $40-$70, while the cost for ProHeart 12 ranges from $60-$130, depending on your dog’s weight.

Tri-Heart Plus: Tri-Heart Plus is a monthly pill that, in addition to preventing heartworm disease, also controls hookworms and roundworms in dogs. These chews have a beef flavor that dogs love, and the cost starts at just $35 for 6 months. Tri-Heart Plus can even be given to puppies starting at 6 weeks of age.

Simparica Trio: For pet owners who want to take care of heartworm, flea, and tick prevention with a single product, we recommend Simparica Trio. This monthly chew also protects against roundworms and hookworms, and can be given to dogs as young as 8 weeks old. At Low Cost Pet Vax, the cost for Simparica Trio starts at $24/month.