Essential Guide to Heartworm Prevention for Pets in Hot Weather

Summer brings sunshine, outdoor fun, and, unfortunately, an increased risk of heartworm disease for dogs and cats. As temperatures rise, so does mosquito activity—the primary way heartworms spread. Protecting your pet with proper heartworm prevention is not just important; it’s essential, especially in warmer months.

In this guide, we’ll explain what heartworms are, why prevention matters more during the summer, and how to keep your pet safe with the proper medications.

What Is Heartworm Disease?

Heartworm disease is a life-threatening illness caused by a parasite known as Dirofilaria immitis. This parasite is transmitted when an infected mosquito bites a pet, allowing the larvae to enter the bloodstream. Over time, the worms mature and settle in the heart, lungs, and nearby blood vessels—primarily in dogs, though cats can also be affected.

Without proper treatment, these worms can grow up to 12 inches long and cause serious complications such as lung damage, heart failure, and irreversible harm to internal organs, often resulting in death.

Why Summer Increases the Risk

Summer weather provides the ideal breeding conditions for mosquitoes. In warm climates, mosquito populations explode, increasing the likelihood that an infected mosquito will bite your pet.

Pets that spend more time outdoors, even for short walks, are particularly vulnerable.

Heartworm Disease Symptoms in Cats and Dogs

In Dogs:

• Persistent coughing
• Fatigue after mild activity
• Weight loss
• Difficulty breathing
• Swollen belly (fluid buildup)

In Cats:

• Coughing
• Vomiting
• Loss of appetite
• Sudden collapse or death (in severe cases)

Heartworm symptoms often go unnoticed until the disease has progressed. That’s why prevention is much safer, easier, and more affordable than treatment.

Why Prevention Is Better Than Cure

Treating heartworm in dogs is costly, painful, and can take several months. Even then, damage to the heart and lungs may be permanent. For cats, there’s no approved treatment, making prevention critical.

Preventive medication is the only reliable way to protect your pet. These medications kill immature heartworm larvae before they grow into adult worms.

Best Heartworm Preventive Medications for Dogs and Cats

Here are some vet-recommended heartworm preventives that also protect against fleas, ticks, and intestinal worms:

For Dogs:

• Simparica Trio – Protects against heartworms, fleas, ticks, and intestinal worms.
• NexGard Spectra – A broad-spectrum monthly chew for fleas, ticks, heartworms, and roundworms.
• Revolution – A topical treatment that covers heartworms, fleas, and ear mites.
• Heartgard Plus – A chewable tablet that prevents heartworm and treats roundworms and hookworms.

For Cats:

• Revolution Plus – Protects against heartworms, fleas, ticks, ear mites, and intestinal worms.
• Bravecto Plus – Offers extended protection for up to 2 months against fleas, ticks, and heartworms.

These medications are easy to administer and are available as chewable tablets or topical applications.

When Should You Start Heartworm Prevention?

Heartworm prevention should be year-round. Consult your vet before starting a heartworm preventive, especially if your pet has missed doses or has never been on treatment. A simple blood test is usually required for dogs before starting heartworm prevention.

Tips to Minimize Heartworm Risk During Summer

• Keep your pet indoors during peak mosquito hours (early morning and dusk).
• Choose pet-safe mosquito repellents specifically formulated for animals to help protect your furry companions from bites without risking their health.
• Eliminate standing water around your home—breeding grounds for mosquitoes.
• Stay consistent with monthly heartworm preventives.

Final Thoughts

Heartworm disease is preventable, but only if you take the right steps. With summer being the peak season for mosquitoes, it’s the most critical time to protect your dog or cat.

Prevention is simple, safe, and affordable compared to the costly and risky treatment of heartworm disease.

Protect your pets with proven heartworm prevention medication today and keep them safe all year long.