Heartworm Disease: What Pet Owners Need to Know
By Lakeshore Road Animal Hospital

Heartworm disease is a serious and potentially deadly condition that can affect both dogs and cats—and it’s more common than many pet owners realize. The good news? It’s preventable with the right care and regular testing.

What Is Heartworm Disease?

Heartworm disease is caused by parasites that are spread through mosquito bites. When an infected mosquito bites your pet, it can transmit microscopic heartworm larvae, which grow into long worms that live in the heart, lungs, and blood vessels.

In dogs, heartworms can grow up to 12 inches long and cause lasting damage to vital organs. In cats, the disease looks a bit different but can still cause serious lung and heart issues—even sudden death.

Why Testing Matters

Even if your pet seems healthy, they could have heartworm disease without showing obvious signs. That’s why we recommend annual heartworm testing—especially before starting or continuing prevention. Testing ensures your pet is protected and helps us catch infections early, when treatment is most effective.

Signs of Heartworm Disease

Dogs may show:

• Coughing
• Fatigue
• Weight loss
• Trouble breathing

Cats may show:

• Vomiting
• Coughing or wheezing
• Sudden collapse
• Loss of appetite

But often, there are no symptoms until the disease is advanced. That’s why prevention is so important.

How to Protect Your Pet

The best way to protect your dog or cat from heartworm is with monthly prevention, either as a chewable tablet or a topical treatment. At Lakeshore Road Animal Hospital, we carry trusted heartworm preventives and offer quick, simple testing. We’re here to help you choose the best option for your pet’s lifestyle and health.

When to Start

Heartworm season starts as early as spring, but prevention should be year-round in many areas. If your pet isn’t already on heartworm prevention—or if you’re unsure when they were last tested—give us a call today. A quick test now can save a lot of worry later.