Heartworm – why prevention is best

Heartworm- Why prevention is best

It’s spring.

And with spring comes mosquitos and concerns about parasites attacking our pups.

Today, I’m looking at heartworm.

A reader recently asked about these nasty worms. 

They wanted to know if they would have to give their dog preventative medication every month for the rest of the dog’s life.

Unfortunately, my research suggests that yes, you do need to dose your dog for the rest of its life.

But first, let’s talk about what heartworm is.

What are heartworms?

What are heartworms?

The heartworm is a parasitic worm carried in certain mosquitos.  When the mosquito bites your dog, it transfers the worm to your dog’s blood.  It’s the same way that people contract malaria from mosquitos.

Once in your dog’s blood, the worm travels to your dog’s heart and the blood vessels nearby. 

When it gets there, it begins to mature, reproduce, and grow.

They can grow up to a full one foot, and an infected dog can have 250 mature worms

As you can imagine, this quickly damages your dog’s heart. 

Plus, your dog’s immune system will notice that there is an invader and begin to try to fight it.  This causes inflammation, which blocks things up faster.

Heartworm blockage in the heart

Heartworm blockage in the heart

With a heartworm blockage, the heart can’t work properly.  

It can’t pump enough blood fast enough to get proper oxygen to your dog’s cells.

Early on, there are nearly no symptoms of heartworm.  It’s not until the worms begin to multiply that your dog starts to have trouble.

Unfortunately, for many dogs, this is about when their guardian realizes there is a problem. 

They notice that their dog isn’t as energetic as they were.  A game of fetch ends after just one or two throws because their dog tires quickly.

Their dog may develop a persistent cough or mild asthma type symptoms.

These symptoms are the body’s way of signaling that it’s not getting enough oxygen. 

They may also have a smaller appetite, vomiting, and weight loss.

If the heartworm isn’t caught in time, the results can be heart failure.

This is the reason your vet wants to test for heartworms at every annual checkup. 

Pros and Cons of testing for heartworms in dogs

Pros and Cons of testing for heartworms in dogs

The earlier the problem is detected, the more likely that the veterinarian will be able to treat your dog successfully.

Their tests are sensitive enough that they can detect a single worm.

The tests have limits though – they can only detect adult heartworms. 

Plus, it can take five to seven months for heartworms to be mature enough to be detected in your dog’s bloodstream.

And by then, it may be too late to avoid what is a dangerous and difficult treatment.

To treat heartworms is expensive and can be dangerous to your dog. 

It can even require surgery.

Really, the best treatment for heartworm is to prevent it.

Heartworm prevention options for dogs

Heartworm prevention options for dogs

When it comes to prevention, I’m pleased to say we have options. 

There are chewable medications that can be taken as a daily, weekly, or monthly treat.

Both Boo & Lorelei take a monthly version, and they love them.  They get excited when they see the box.

There are also topical treatments that you apply to your dog’s skin. 

There’s a newer option now, too.

You can ask your vet about a vaccination that your dog receives twice a year.  This frees you from having to remember to dose your dog.  And is a safe and well-tested prevention method.

These medications are incredibly effective – but nothing works 100%.  That’s why your vet still asks for annual testing even if you’re already using a preventative treatment.

It may seem redundant to you.

But isn’t it worth it to know your furry baby is healthy?

One important note.  Normally, I advocate for natural prevention methods where possible.  But not in the case of heartworm.

NONE of the natural options I researched are proven effective. 

In fact, some even proved harmful to our dogs.  So, please stick with veterinarian approved prevention treatments in this case.

For more posts on health and safety, check out Canine Leukemia – natural ways to help your dog cope and Pup Finance – Be Prepared for Emergencies.

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Hi! My name is Heather Hallman. I’m the mother of two beautiful girls and a MAJOR passionate pet parent. I can hardly wait to bring you the BEST resources and information that I've found for our fur-babies.