Puppy Care Guide

Week 33 – Heartworm & Parasite Prevention

“Protection from the inside out — prevention today ensures a healthy tomorrow.”

After completing vaccinations, it’s time to safeguard against internal and external parasites. Even healthy-looking puppies can carry organisms that quietly affect the heart, lungs, intestines, and skin. Let’s explore what they are and how to keep your dog protected year-round.

What Is Heartworm Disease?

Heartworm disease is a mosquito-borne infection that targets a dog’s heart and lungs. Once bitten by an infected mosquito, larvae travel through the bloodstream and mature into long worms inside major vessels.

Persistent dry cough
Fatigue or exercise intolerance
Loss of appetite or weight loss
Difficulty breathing or general weakness

💡 PetGo Tip: Prevention is far safer and cheaper than treatment — once infected, dogs require months of rest and expensive therapy.

🦠 Internal & External Parasites

Dogs can also be affected by roundworms, hookworms, tapeworms, fleas, ticks, and mites. These can cause itching, skin infections, anemia, or digestive issues — and some can infect humans too (zoonosis).

🌱 Did You Know? Parasite eggs can survive in soil for months — prevention protects your pet, family, and community.

🩺 When to Start Prevention

Prevention can start as early as 8 weeks old — and it’s never too late to begin. Heartworm risk peaks from April to November in most of Canada, but year-round coverage is best for outdoor dogs.

Indoor pets aren’t exempt — parasites can enter through shoes or open windows.

💡 PetGo Tip: Use the PetGo Health Tracker to mark monthly prevention dates — consistency is the key to protection.

💊 Common Preventive Medications

1️⃣ Heartgard® (Oral)

A chewable tablet that prevents heartworm and controls roundworms and hookworms. Combine with a flea/tick treatment for full coverage.

💡 PetGo Tip: Perfect for dogs who prefer simple monthly chews.

2️⃣ NexGard Spectra® (Oral)

An all-in-one monthly chew protecting against heartworm, fleas, ticks, and intestinal worms. Convenient and widely used across Canada.

🌟 Think of it as a complete shield in one tasty dose.

3️⃣ Frontline® (Topical)

A spot-on solution applied to the skin to target fleas, ticks, and lice. Many owners pair Frontline with Heartgard for comprehensive coverage.

⚠️ Avoid bathing or swimming for 48 hours after application and wash hands after use.

Choosing the Right Dose & Seasonal Plan

Each product comes in weight-based doses — too little won’t protect, too much may cause side effects. Confirm your dog’s current weight before every refill.

During summer, full-spectrum prevention like NexGard Spectra is ideal; in winter, some owners use only Heartgard for heartworm focus. Consistency is what matters most.

💛 PetGo Reminder: Re-check weight monthly — puppies grow fast and need updated doses.

⚠️ Important Safety Notes

Mild side effects like temporary lethargy or appetite loss can occur. If vomiting or weakness persists, stop the medication and contact your vet.

Outdoor dogs are more exposed — perform tick checks after every walk, especially around ears, neck, and paws.

💡 PetGo Tip: Run your fingers through your dog’s coat after each outing to detect ticks early.

Preventing Before Problems Start

Proactive care keeps your dog healthy and energized. Consistent heartworm and parasite prevention means fewer vet visits and a longer, happier life.

💛 PetGo Reminder: Prevention is not optional — it’s a lifelong promise of care and trust.

Continue with PetGo’s Puppy Care Guide

PetGo helps you track monthly parasite prevention and vet reminders so your puppy stays protected year-round.

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