8 Best Heartworm Prevention For Dogs in 2020

For protection against the nasties your beloved pooch can pick up from anywhere, you need quality protection. The best Heartworm prevention for dogs will stop you from needing expensive vet care later and will ensure your dog is up to date with their defenses against some uncomfortable nasties. This disease can be deadly so to stop the likes of mosquitos, it is best to be prepared.

The following products in our top 8 list will all do a great job of preventing Heartworm but also other diseases by increase cardiovascular health. Some last longer than others whilst some are easier to apply. Whatever approach you take, they are all effective at preventing Heartworm.

Here are our top 8 picks for the best Heartworm Prevention For Dogs:

#8 Bayer K9 Advantix II

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This product offers protection for large dogs against fleas, ticks, and mosquitos. The latter is what should be most concerning when it comes to Heartworm prevention for dogs so getting this into your dog’s system is crucial. It kills the pests on contact so they can’t bite to transmit diseases or cause irritation and works within 12 hours of first applying. Each application will last 30 days and is easy to apply via the topical liquid. It’s waterproof and effective so you’ll get proven protection for your dog.

Pros: Works fast
Kills mosquitos on contact
Works on fleas and ticks too

Cons: Only for large dogs

#7 Zesty Paws Allergy Immune Supplement for Dogs

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Sometimes the best way to prevent a health problem from getting worse is to protect the dog by boosting their immune system. These high-quality chews feel more like a treat for the dog as they are lamb flavored but its what inside each one that is impressive. They contain omega-3 and probiotics to help support immune health. With apple cider vinegar and other careful selected ingredients that can give your dog the antioxidants it needs to maintain a healthy immune system. The bonus is what I can do for your dog’s coat but it is just a good supplement to sneak into their diet.

Pros: Boosts immunity
Dogs like the flavor

Cons: Not a direct Heartworm prevention

#6 TevraPet Activate II Flea and Tick Prevention for Dogs

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You can buy this in different strengths to suit the size of your dog and give them protection against fleas, ticks, and mosquitos. As with most of these products, it should not be used on other pets such as cats but it is a vet quality formula that is easy to apply and will still work after your dog gets wet. It’s another Heartworm prevention for dogs that kills the mosquitos on impact so you don’t have to wait for them to bite before they die. A lot of people comment on the value you get from this product and that it is made in the USA.

Pros: Kills mosquitos on impact
Made in the USA

Cons: Have to apply over a larger area

#5 Bayer Animal Health K9 Advantix II Small Dog 4-Pack

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For small dogs, this 4 pack repellent of mosquitos, as well as fleas and ticks, will help to prevent Heartworm from ever being a problem. It starts to work within 12 hours and kills fleas before they can even lay eggs. Keep your cute pooch protected with this effective formula that kills mosquitos on impact. It gives your dog four months of protection and is easy to apply via the tube, giving you the confidence to know you can safely leave your dog at home and mosquitos won’t be a problem.

Pros: Works fast
Kills mosquitos on impact

Cons: Not for medium or large dogs

#4 SafeBay – Milk Thistle for Dogs and Cats

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This is fine to use on both dogs and cats and helps your pets’ detox system by offering liver and kidney support. You can add it to their food to give their immune system a boost which will help them in the event of a mosquito bite. It is known for cleansing toxins and removing free radicals from your dog which can lead to something more serious later down the line. It’s not strictly for preventing Heartworm but will give them a boost and a better chance of fighting the disease.

Pros: Easy to get into your dogs system
Natural ingredients

Cons: Not directly for Heartworm prevention

#3 Nutrition Strength Cardio Support for Dogs

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Because they attack the heart, your dog needs a better cardiovascular system. These tablets are easy to get into your dog’s diet and can be taken daily. With 120 in a pack, you are getting a three month supply (depending on the size of your dog – bigger dogs will need more tablets – see bottle) that includes some quality ingredients such as L-carnitine, Coenzyme Q-10, Vitamin E, L-Taurine, and more. These are great for improving blood flow, heart health and function, improving oxygen circulation, and beyond. They are suitable for all dog breeds and sizes and made in the USA.

Pros: Up to 3 months supply
Quality ingredients
Natural formula

Cons: Only lasts a month for large dogs

#2 Wondercide Natural Flea, Tick and Mosquito Control for Dogs

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This offers an effective way of protecting your home against the likes of mosquitos, ticks, and fleas, not just your pets. When it comes into contact with any of these pests, it kills them on contact and it a natural product so safe to apply straight to your pet’s coat. This might be easier than getting them to eat a chew so depending on your dog’s preference, it can be great to have as an option. It has a lemongrass scent that is pleasant and can be applied to carpets and furniture to protect different areas of your home. A Heartworm prevention for dogs, and pest prevention for the family.

Pros: Kills pests on impact
Works within 2 minutes
Can be applied to carpets and furniture

Cons: Needs to be applied every 2-3 days

#1 VECTRA 3D 6 Pack Blue for Medium Dogs

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Great for medium dogs over 8 weeks of age, this trusted formula is known to kill mosquitos, eliminating the risk of Heartworm. It kills pests on impact and works on mosquitos but also fleas, ticks, mites, and other pests. It is waterproof so even after you apply, your dog can get wet and it will still work to protect him or her. It dries fast and is effective for around a month so you get a 6 month supply with this product. Because it can only take one bite from a mosquito to seriously put your dog in danger, this is the sort of protection they need all year round.

Pros: Kills mosquitos on impact
6 month supply
Dries fast and waterproof

Cons: Can be expensive for some people

More products also worth checking out:

Heartworm Prevention For Dogs Buyer’s Guide

We all want the best for our furry friends, and the easiest way to ensure they live a long and healthy life is to give them the protection they need from certain diseases. This is where heartworm prevention for dogs becomes so important. Not only is it a potentially deadly disease, but it is easy to protect your dog against it.

To help you find the ideal product, we have created the following buyer’s guide. By the end of it, you’ll be able to make a sensible decision.

What To Look For In Heartworm Prevention For Dog’s

Fast Working

As with any preventative measure, you want it to work as fast as possible. You may have a walk in the nearby fields in mind, a place where the likes of mosquitoes (which can potentially house heartworm) may be. Most products tend to work within 12 hours and anything much longer than this is unnecessary.


The formula for most reputable brands will include prevention for other nasties such as fleas and ticks. This can help put an owner’s mind at rest, but also save money on multiple treatments. Heartworm prevention for dogs should be able to kill fleas and ticks on impact and get rid of any existing eggs as well. Again, you will want this to be fast-acting and long-lasting. Which brings us to…


No one wants to have to spray their dog every day to ensure they are protected, thankfully, this is something that most brands avoid. One application usually lasts a few months, or at least one. To help make it easier to remember, mark the next treatment on the calendar so you can ensure your pooch is always protected. 

Easy Application

Most products will be either a chewable tablet that can go inside a treat or among their meal or via a tube that drops a liquid, usually onto the back of the neck. A spray or other method can be distressing for a dog. 

The Right Strength

This is worth paying attention to since aq formula designed for a small dog will not be strong enough for a large breed. On the other side of this, using a formula that is too strong for a small breed is not a good idea. This is why most brands make their products with different dogs in mind. This ensures that houses with dogs of different breeds can use brands and products they trust.

What Is A Heartworm?

Spread from mosquito to a dog upon a bite, this is a type of roundworm that is a parasite and can lead to expensive vet bills and could even be fatal. It is the female heartworms that produce offspring inside a dog that make their way into the bloodstream. This can result in some nasty side effects, which we will go into now.

What Are The Symptoms?

The symptoms depend on the number of worms that are living inside the dog. If they have had months to multiply, then expect the symptoms to be worse. It may not be obvious straight away and some of the symptoms of the early stages can include an occasional cough which may not usually be cause for concern on its own.

One of the most common symptoms is tiredness, especially if it is persistent, as is any sign of difficulty when breathing. Also, heart failure, a lack of energy are common. Since heartworm can cause lung disease and failure, it is important to consult a vet if you suspect your dog has any of the above. 

Can A Dog Transmit Heartworm To Another Dog?

No, it cannot. Heartworm can only be transmitted via a mosquito bite so one dog being close to another is not enough for it to transmit heartworm disease. 

Can Cats Get Heartworm Disease?

If you have other household pets including cats, ferrets, there is a chance that they too can contract heartworm disease, but not from your dog. The worms do not tend to survive as well inside a cat’s body as they do in a dog which is why cases are less common.

Is There A Treatment For Heartworm Disease?

For dogs, there are certain treatments available that are approved by the FDA. These are capable of treating infections that tend to work better the earlier heartworm has been diagnosed. This can be via injection or other methods such as a topical solution but the strength and type of treatment will vary depending on the severity and should be recommended by a vet.

Treatment may start with a series of blood tests, as well as X-rays to examine the severity. This is why prevention is the best form of ensuring your dog is protected. A simple and cheap alternative to what can be a painful time for a dog is heartworm prevention for dogs. 

What Is The Best Heartworm Prevention For Dogs?

Having considered the reputable products available, we found VECTRA 3D 6 Pack Blue Dogs to be best. It is available in different strengths for most dog breeds and is fine to use when over 8 weeks old. The 6 months supply is easy to apply and dries quickly. Not that this matter too much as it is also waterproof so there is no risk of it being washed off. 

Because it also kills fleas, ticks, and mites among other nasties, it is a bit of an all in one formula. Each application lasts a month and it is also a good value compared to a lot of the competition. 

How Long Does Heartworm Prevention For Dogs Last?

This varies depending on the product, but most tend to last around a month before you need to re-apply. The easiest way to do this is to set a reminder on your phone, apply on the first of every month, or write it on the calendar. Be sure to read the instructions of any brand you are suing for the first time as the length of protection can vary.


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