Heartworm in Dogs

Heartworm in Dogs
October 8, 2018

What Exactly is Heartworm, Anyway?

You’ve probably figured it out; the name says it all. ‘Heartworm’ is caused by a ‘worm’ like parasite, affecting the heart. But that is only the most basic explanation.

Heartworm disease is a very serious, potentially fatal disease that affects countless animals in addition to household pets. The disorder is caused by foot-long roundworms (similar to pasta noodles- to the human eye) that live in the heart, lungs, and other blood vessels.

Symptoms of Heartworm

The best way to know whether or not your pet has heartworm is to test for it in a veterinary setting, and offer monthly preventative. Even so, the disease has likely progressed to a very dangerous point if you’re able to see symptoms arise at all. That being said, symptoms include:

Mild, persistent cough

Decreased appetite

Weight Loss

Heart failure

Swollen belly


How Can Dogs Get Heartworm?

When a mosquito decides to grab a quick blood meal from an infected animal, microscopic baby worms that circulate the animal’s bloodstream, called microfilariae, are picked up along with the blood taken. 

Over a period of 10-14 days, these microfilariae mature into an infective stage. When that same mosquito bites a dog, cat, or other animal, these worms now can enter the new host through the bite wound.

  • It takes about 6 months for the larvae to mature into adult heartworms once inside a host.
  • Mature heartworms can live for up to 5-7 years in dogs and 2-3 years in cats.

What Can Heartworm Do to My Pets?

Simply said, heartworm disease can cause damage to the heart, lungs and arteries, possibly affecting your pet’s health long after the worms are gone. If left untreated, numbers can increase; pets/animals have been known to harbor several hundred worms in their bodies.

Adult heartworms can cause major problems by actually clogging vessels leading to and from the heart, as well as the valves of the heart. This can inevitably lead to death if left untreated, and has often resulted in death if not treated in time.

Unfortunately, by the time clinical signs and symptoms become apparent, the disease is already at an advanced stage. For this reason, monthly heartworm preventative is your best treatment- before your pet ever has a chance to get sick!

How Can I Prevent Heartworm?

Countless heartworm medications are easily available for our pets these days, usually requiring a prescription from a licensed veterinarian. Of course, these prescriptions almost always require mandatory heartworm testing. In the end, heartworm medication is the absolute best way to prevent the spread of the disease.

  • Mosquitos are the only vector to transmit this disease.

Some known Brands:




  • Ask your veterinarian about ingestible that lasts an entire six months, now available!

Q: Can I just use Mosquito Repellant? 

A: Absolutely not! First and foremost, most insect repellants are toxic to our pets, animals that like to groom by licking their fur.

Whether it is in the form of a topical ointment or an ingestible ‘tablet’, the medication is designed to work actively at a constant rate until the next recommended dose. Insect repellant will only work for a short time, isn’t always effective, and almost certainly won’t make it past your pet’s coat 100% of the time.