Risks vs. Benefits of Flea, Tick & Heartworm Preventatives: Are they Helping or Harming? An in-depth look, Plus Natural Alternatives!

Preview: Still giving monthly flea, tick & heartworm preventative products?! Are you giving them year-round?! The information in this post may have you heavily questioning your decisions and the safety of these pesticides (Frontline, Nexgard, Seresto, Bravecto, Pet Armour, Hartz, and more)! This may be the most in-depth compilation of research that has ever been put together on this subject. Many articles have been written on these topics separately, and there's so much information out there, often with no sources linked for pet owners to do their own research! I wanted to change that. I want YOU to be fully informed when working with your veterinarian! Especially since conventional flea & tick preventative products are linked to neurological side effects, including seizures, and even death! Yes, the FDA has sent warnings to veterinarians and consumers. In fact: one dose of a topical flea and tick product is enough to kill 60 MILLION bees. This is a long read, but it is packed with research, and also includes NATURAL ways to protect your pets, and your entire family! Not only will you gain insight on the dangers of conventional products, I'll walk you through the best ways to boost your pet's immune system with nutrition, plus you'll learn which herbs you should be planting in your yard to repel these pesky critters! Please be aware: depending on your pet's health history and your geographic location, lifestyle, etc. You may opt to use conventional forms of parasite control. And that's okay! Just know: It is so very empowering to be informed no matter which method you choose! I want to be sure YOU and YOUR PETS have Happy Trails! For another sneak preview, click here. Are you ready to feel confident and empowered in your pet's healthcare decisions?! Now is the time! Let's get started.

Pesky bugs are not fun!! We all know this!

So naturally, many owners want to prevent them from bothering and even inhabiting your pet, and house!

Mosquitoes are annoying, ticks can carry disease, and fleas can lead to very unpleasant itching and even allergic reactions called flea allergy dermatitis.

Mosquitoes can transmit Heartworm.

Ticks can transmit diseases such as:

Tick paralysis can also occur. This can be tricky to identify, but is becoming more commonly known.

When ticks bite an animal or human, they can transmit certain bacteria that may cause the tick-borne disease.

Tick-borne diseases can range from asymptomatic to quite severe, depending on the health status of the individual.

The most common symptoms include:

When I was first taught about these diseases and the preventatives, I was told the prevention is safer than the disease. Why not? Sounds true, right?

At the veterinary clinics I worked at, we had drug company representatives come in often with big boxes of donuts to sell us their preventatives, give us free doses for our pets, and so on (I admit: I loved those days)!

Recently more and more warnings have been surfacing about the dangers of flea & tick preventative products. Which of course, made me question and begin researching,

Unfortunately, in wanting to protect are pets, we are often confronted with heavy marketing (such as free stuff, discounts and even donuts), and a strong push of buying potentially dangerous pharmaceuticals with the use of fear-mongering.

Without being given only a small amount, if any, warning on their potential dangers (unless you choose to read the drug insert that is provided in each box).

"Common side effects of these medications: Vomiting, lethargy, seizures, kidney damage, and even death."

*You can read a more in-depth article on the prevalence of Lyme and the dangers to each of the most common medications HERE.

Did I recommend these drugs to clients?

Yes.

Did I use them for my own pets?

You bet!

Personally, I would not use them in cold seasons because I wanted to give my dog's system a "break."

But, I do not use any conventional products for parasite prevention anymore.

Many professionals now recommend them YEAR ROUND!

*My first dog was given year-round preventative and still got 2 different tick-borne diseases.

Now, in this post I'm going to present some information that may be overwhelming, but I want you to know that I support your decision to use whichever method of parasite prevention you feel is needed for your pet. Some animals may do better on certain products rather than others. And I've known many dogs and cats to be completely fine using these products. But sadly, some have severe reactions. I'm here to help you make an informed decision for your dog, cat, environment, and ultimately your entire family.

* The FDA issued a warning on these products most recently in 2021.

The main drug causing an uproar of harm to pets recently is called Isoxazoline. It is the main ingredient in some flea & tick preventatives, and is a GABA (gamma-aminobutyric acid) receptor antagonist.

When a flea & tick preventative is given topically, or orally, to a pet...the active medication is absorbed and enters the pet's bloodstream.

The mode of action is that when a tick bites the pet, the medication enters the tick and acts as a NEUROTOXIN. Binding to chloride channels, then blocking nerve signals… which paralyzes the tick, and ultimately kills it.

Sounds simple enough.

Well, if we put our thinking caps on... Something should CLICK....

You might ask, "Why are we introducing a poison into our pet's blood, to kill these insects once they attach? "

If this chemical acts as a neurotoxin to the insect.... What wouldn't make it a neurotoxin to a larger animal...

Say, a cat or dog...?

A toxin is a toxin!

Given the extensive use of these drugs, over long periods of time makes me wonder...

Is this a cause of epilepsy and other neurological disorders in pets? Well, according to the FDA warning, this very well could be true.

Reports of seizures and dying pets have heavily surfaced in recent years.

Keep in mind, when using spot-on treatments (such as Frontline) your dog or cat can shake off, rub on furniture, roll on your bed, etc... Now, these chemicals get onto you, and your kids!

Recently, researchers in the the UK investigated the effect these chemicals have on the environment.

One active ingredient used in flea and tick preventatives is an insecticide called Fipronil, it was found in 99% of samples and a very toxic breakdown product called fipronil sulfone was found in 97% of samples.

That is up to 38x higher than chronic toxicity levels!

WOAH!

Imidacloprid, another toxic nerve agent, was found in 66% of the river samples and was above toxicity limits in 7 of the 20 rivers that were tested.

Fipronil was banned for farm use by the EPA, but we put it on our pets?!

Just how powerful are these chemicals?

"One flea treatment of a medium-sized dog with imidacloprid contains enough pesticide to kill 60 million bees."

"Currently, the flea treatments are approved without an assessment of environmental damage."

-Source.

Fipronil has also been shown to cause cancer in dogs, and is a possible carcinogen to humans.

(Fluralaner) This one has only been out for a few years and has caused quite a bit of chaos already. In 2020, the FDA approved Bravecto Monthly Chews for 8 WEEK OLD PUPPIES.... Weighing as little as 4.4 pounds.

Can you imagine giving an 8 WEEK old baby a systemic neurotoxic insecticide every month?!

Does this not sound crazy?! This is outrageous to me.

FROM THE LABEL:

"Fluralaner is a member of the isoxazoline class. This class has been associated with neurologic adverse reactions including tremors, ataxia, and seizures. Seizures have been reported in dogs receiving isoxazoline class drugs, even in dogs without a history of seizures. Use with caution in dogs with a history of seizures or neurologic disorders."

BRAVECTO is also available in EXTENDED DOSE for dogs 6 months of age and up!!

The difference? ..... Nearly TRIPLE the dose of neurotoxic medication.

11.4mg/lb compared to the 4.5mg/lb monthly chews.

Numerous side effects along with birth defects were reported from their studies.

I stumbled upon this in a store a few weeks ago, and was floored by the warnings, hazards, and precautions.

Can somebody please tell me why and how this product was ever approved for use on pets if it is SO TOXIC?!

View Class Action Lawsuit HERE.

Another popular product is flea & tick collars. I HIGHLY DISCOURAGE against these.

Not only are these toxic chemicals coming into contact with your pet, but they rub off on your clothes, your bedding, and eventually make their way onto your skin and even your kids!

With warnings like:

"Avoid contact with eyes, skin or clothing."

"Wash thoroughly with soap and water after fitting collar."

Along with multiple warnings against children touching the product..

These are legitimate chemical pesticides. Please, don't use them, especially with kids in the house.

New warnings are coming out against these products what feels like daily.

The most recent uproar as of March 2nd, 2021:

"The EPA has done nothing to inform the public of the risks."

-USA Today.

BUT, people aren't aware that the FDA has warned about the dangers with flea & tick medications. They did not issue one specifically for Seresto, but many of these drugs work in the same matter to KILL insects as you've learned above... So, couldn't we assume that feeding our pets year round, neurotoxic insecticides maybe isn't a good idea?! Maybe, just maybe, the drug could build up in the pet's system and cause the same death inducing effects as it does on those insects?!

"Seresto, one of the most popular flea and tick collars in the country, has been linked to hundreds of pet deaths, tens of thousands of injured animals and hundreds of harmed humans."

- Source.

- Document of Seresto injuries and deaths.

Sometimes, you may run across studies 'proving' that these products are 'safe...' but tread lightly and do some digging... You may find that the research is fully funded by those who make and/ or sell the product.

-Source.

UPDATE FEB 2024:

VIEW SERESTO CLASS ACTION LAWSUIT AND $15 MILLION SETTLEMENT!

Additional Seresto Lawsuit Settlement info

A brand I have seen great harm from. There have been countless cases of severely injured pets. Including seizures, burned skin, and death. A quick search and you will find Facebook pages dedicated to this by pet owners who's pets have suffered injuries or death, as well as an entire website for Hartz Victims.

Read other product Risks & Recalls HERE.

Most commonly found in the southern states, heartworm is exactly how it sounds. A worm that infects and essentially suffocates heart function, if the disease progresses far enough.

*View a map of USA heartworm incidences here.

Heartworm 'preventatives' are marketed with this scary term! Unfortunately, these too can come at a cost.

These 'preventatives' do not actually prevent infection. The main ingredient is Ivermectin, a systemic parasiticide.

This is a low-dose treatment, not a prevention.

Shortly put, when a mosquito bites an animal, it can transmit microfiliae (the little 'bugs' that grow into the big heartworms). This drug kills the microfilariae.

So essentially, you are treating your pet year-round for parasites they likely don't even have. Wouldn't it be more logical to just repel the bugs that transmit these infections?

Some pet owners might prefer this chewable medication because it has de-wormer in it as well, preventing intestinal parasites like hookworms. Again, treating for a parasite they likely don't even have. If you are concerned about intestinal parasites, opt for a yearly fecal test.

You can read a more thorough overview of what Heartworm is HERE.

The most common side effects of chewable heartworm medications that I've seen are:

ProHeart6 was an injection for dogs that was said to protect them from heartworm for 6 months. It was only on the market for 4 years due to terrible side effects including a string of deaths, before it was pulled! Later, it was reintroduced, and now there is a stronger, and longer acting version called Proheart12!

Parabens? Really?

I recently saw a post on Facebook by someone whose dog dearly died after getting a ProHeart6 injection along with the Rabies vaccine and the Distemper Combo all in one visit.

The insert actually says:

"Use caution when administering PROHEART 6 concurrently with vaccinations. Adverse events, including anaphylaxis, have been reported following the concomitant use of PROHEART 6 and vaccines."

What's worse is that veterinarians actually have to take a Risk Minimizing Action Plan (RiskMap) in order to use this product in their clinic.

The inserts say:

"ProHeart 12 and ProHeart 6 are for use in dogs only and are available through a restricted distribution program to veterinarians that have completed the RiskMAP training and certification module."

Read the full ProHeart6 product insert HERE.

Read the full Proheart12 Product Insert HERE.

A little known fact: some breeds of dog can have genetic mutations that allow the active drug in these medications to cross the blood-brain barrier. This can cause toxicity and potentially lethal neurological damage. Herding breeds in particular are known to possess these gene mutations making them highly susceptible to adverse reactions from Ivermectin. Please discuss this with your vet to make a fully informed decision, and consider getting a DNA and Health Test done on your dog to see if they are at risk.

Over the past few years, a LOT of new information has surfaced about the benefits of ivermectin use! From viral al infections, to parasites, and even cancer! I would highly encourage you to look into this subject more!

I advise against this one for many reasons.

Lyme Disease has been marketed to be extremely terrifying for pet owners.

We went from the recommendations:

"Give preventatives only in summer months."

To "Give preventatives year-round, test every year, and give a vaccine every year."

But is Lyme Disease really so dangerous?

Here's a passage from an article in the Journal of Veterinary Internal Medicine:

"What has not changed is the finding that most Bb-seropositive dogs and cats show no clinical signs of illness, neither experimentally (using the natural tick exposure model) nor in the field. Signs of Lymearthritis, seen in a small subset of infected dogs, are transient or respond quickly to PO antibiotics. Signs of dermatologic, neurologic, orcardiac manifestations as seen in human patients are rare and not well-documented in dogs or cats. The most serious (putatively associated) form of LB in dogs, Lyme nephritis, is less common than Lyme arthritis. No experimental model to study its pathogenesis, treatment, and pre-vention in over-represented (retriever) breeds has been developed, and no validated staining techniques are available to prove that glomerularimmune-complexes are Lyme-specific in kidney biopsy specimens from living dogs."

My personal experience: I have seen probably 80% of dogs come up positive for Lyme at some point after receiving the Lyme vaccine. Makes sense, because the vaccine is only 80% effective.

But scariest of all, is many of them (whether positive or not) developed joint issues, arthritis, and/or acute kidney disease. Which are now known side effects of the vaccine itself. Pretty ironic that we are vaccinating against a disease that causes arthritis and kidney disease, with a product that causes arthritis and kidney disease...

So, is the dog having an autoimmune reaction to the vaccine? Or are they now infected with Lyme Disease anyways? Hard to tell. And rarely is it looked into, but there is evidence that the vaccine-created antibodies interfere with testing markers. Testing for Lyme disease isn't as simple as it sounds... we cannot often differentiate a true infection versus exposure, as both will create antibodies.

This can lead to unnecessary treatment with antibiotics, steroids and other medications for pain and inflammation, and further issues down the road.

And, this still doesn't protect your pet from any of the other tick-borne diseases..

Meryl Littman, lead researcher at University of Pennsylvania’s School of Veterinary Medicine states:

“95% of exposed dogs don’t get sick, but they become Lyme antibody-positive on tests, which may scare people into thinking they need to be treated.”

She also says:

"One of the worst kidney diseases a dog can get is an immune-mediated glomerulonephritis. It is mostly seen in Labrador and golden retrievers. We don’t know whether the Lyme vaccines could make an immune-mediated disease worse, and so I prefer not to use them.”

The Lyme vaccine was fast tracked to market for use in pets in the 90's, and had many veterinarians concerned over its safety.

"Some leading veterinary scientists, alarmed by the rush for a magic answer to what they feel is sometimes an inflated fear, have urged that the vaccine be used sparingly until more is learned about its effectiveness and long-term safety."

- Source.

Not only that, but we know vaccines contain toxic ingredients, like aluminum, formaldehyde, and mercury. How are known neurotoxins and carcinogens keeping our pets healthy?

Lastly, the Lyme vaccine was marketed for humans a few years ago, and was highly unsuccessful. It had many lawsuits and numerous side effects; So much so that it was actually completely withdrawn from the market... So, I guess now they just convince people to give it to their pets...

One last note: Almost all veterinarians offer and recommend for a yearly Lyme vaccine.

But is it needed? Is it effective?

Here's the actually insert from the manufacturer that I printed off:

This insert states:

"The need for annual revaccination has not been established."

Then why are we doing this every year?!

*You can read more abut the effects of over-vaccination and the risks associated with it in this 3 part series on bordetella.

And, as with every other vaccine, it has a disclaimer of:

"This product has been shown to be efficacious in healthy animals. A protective immune response may not be elicited if animals are incubating an infectious disease, are malnourished or parasitized, are stressed due to shipment or environmental conditions, are otherwise immunocompromised, or the vaccine is not administered in accordance with label directions."

So again, if your pet is already having a potential active infection.... they should not be vaccinated with this.

Personally, I have never and will never give this one to my pets.

With a yearly recommendation in testing for Heartworm infections, Lyme and other tick-borne diseases using a 4DX in house test, we can be certain that it would likely be caught early if a dog or cat was exposed. This test looks for antibodies to specific diseases, with few drops of blood and takes about 10 minutes to run.

I have, in some instances, seen veterinarians recommend the Lyme vaccine whether a dog is positive for Lyme or not. Why are we giving a vaccine for a disease that the pet already has or has been exposed to? My humble opinion; the immune system is already at work fighting it, let's not introduce anything more.

I'll reiterate from above: testing for Lyme disease isn't as simple as it sounds... we cannot often differentiate a true infection versus exposure, as both will create antibodies.

If a pet does come up positive on a 4DX test, veterinarians usually reserve treatment with antibiotics ONLY for symptomatic pet. Which I highly advise!

If the pet has come up positive but shows no symptoms of the disease, this is showing that they have successfully created the appropriate antibodies and their immune system took care of it before unpleasant symptoms could arise.

"Serological screening of healthy dogs is controversial because it can lead to overdiagnosis or overtreatment of normal dogs, most of which never develop Lyme disease. However, serological screening can provide seroprevalence and sentinel data and stimulate owner education about tick infections and control. Although it is unknown whether treatment of seropositive healthy dogs is beneficial, the consensus is that seropositive dogs should be evaluated for proteinuria and other coinfections."

As stated above in this study, pets should still be monitored for coinfections and organ damage from these diseases if a positive result does occur. Tick-borne diseases can be especially hard on the kidneys.

I do test my dog yearly, and if anything were to come up.. at least I have a baseline and can monitor for any signs of active infection or other health issues potentially related to the given disease.

Proper nutritional support and supplement should be utilized always!

A very common concern I see!

The most common mistake: Treating the pet, and NOT treating the environment!

Fleas thrive in shady, cool spots outdoors (bushes, under decks and porches, etc.). So areas with long hours of direct sunlight will not need to be treated as heavily.

A large problem with natural flea treatment is that people are so adamant on only using natural products, that they needlessly prolong their pet's suffering for MONTHS on end instead of just using a conventional flea treatment to put an end to the infestation. Fleas are absolutely miserable. But when it comes down to it, we must think of our pet's overall quality of life, and our own sanity in the matter!

Lets get down to business!

How can we naturally protect our pets from fleas, ticks, mosquitoes and other insects?!

Unfortunately, some marketed products claiming 'all natural' are far from safe!

Please be aware of this!

I have noticed some scary warnings on various "natural" products, plus underlying harsh additives, and unsafe essential oils such as Pennyroyal. Some contain peppermint and clove, which can be 'hot' and irritating to a pet's skin, especially if the oils are poor quality, adulterated, or not in proper dilution.

So use caution, and read labels carefully.

Natural does not mean safe!

This includes the use of Diatomaceous Earth (DE), which is harmful to the gut and can be detrimental if inhaled. I never recommend or advocate for the use of DE!

That being said, there definitely are safer alternatives out there!

First, we can help protect our pet by assisting the body and allowing them to thrive through nutritional support and alternatives therapies.

Even though cats and dogs are carnivores, that doesn't mean they can't benefit from you adding some fresh, organic fruits and vegetables. These will provide many phytonutrients and antioxidants that most processed diets often lack. Some of my favorite brands of food that I recommend are listed here!

Various supplements can also be added to nourish the body, such as herbs and probiotics.

In the spring, I usually bump up her antioxidant levels and detox her gently for a few weeks while giving extra probiotics. Since I DO NOT give conventional Flea, Tick & Heartworm medications, it's very important that I keep her body's internal environment free of toxins and inflammation!

Poor health status and chronic inflammation creates an ideal environment for parasites and disease to take hold.

To keep your pet in optimal health, I recommend light detoxes throughout the year. Our pets are consistently exposed to environmental toxins just as much, if not more than we are. I use a variety of supplements to support natural detox with my pets and with my Clients.

In order to detox appropriately, your pet needs to have a high quality diet already established in order to proved the correct nutrients for detox pathways to work correctly.

I love adding medicinal mushrooms to my dog's diet. Mushroom blends that are pure & potent have an incredible immune boosting and even cancer fighting ability! Every pet should be provided with medicinal mushrooms as a regular dietary supplement! You can purchase medicinal mushrooms for your pets (and yourself!) here.

This kit includes 2 remedies: Ledum 30C, for use with acute tick bites.

And Borrelia 200C: A prophylactic remedy to use for protection, to help the animal build a natural immunity.

You can also purchase single remedies here.

Or you can purchase kits here.

Ledum has a long history of being helpful against all tick diseases. While homeopathic remedies come in varying potencies, but unless you're working with a profetional homeopath I suggest with sticking to 30C or 200C. Dosing can vary on the number of pellets you give and how often. But generally a remedy for an acute illness or injury is given 2-3x/day for 2-3 days OR until symptoms resolve.

Homeopathic care is a great tool overall in strengthening the body's vitality and decreasing susceptibility to illness.

Some methods of insect repellent would include:

Please do your research on garlic for dosage amount and safety precautions.

Personally I feel everyone should consume fresh garlic daily. It has MANY potential benefits including; lowering cholesterol, boosting immune system, anti-viral properties, fighting tumors and even cancer! It has been shown to control and kill parasites in mice!

The garlic smell is said to be excreted through the animal's skin and repels the unwanted insects. But overall, it generally just boosts the immune system to make your pet less appealing to insects.

In order for garlic to prove toxic; a 10 pound dog would have to eat about 8 whole cloves.. A 75 pound Golden Retriever 60 cloves. Yes, excessive amounts can be toxic. Especially a concentrated extract.

I personally use Young Living oils. This link provides general safety guidelines for pets.

My favorites to use are: Cedarwood, purification, lavender, thieves, and lemongrass.

I properly dilute them via my Bug Off Recipe into a spray using distilled water, and witch hazel (some people add apple cider vinegar.

We both get a spritz before we head out for a hike, reapplying often! Remember, natural remedies are short lasting.

Mosquitoes will not even land on my dog when I use this spray! Though, their hovering is enough to be of annoyance!

This also doubles as a handy itch relief spray, should a bite occur!

BUG OFF RECIPE:

You will need:

1oz Glass Amber spray bottle

1/2 oz of distilled water

1/2 oz witch hazel (I use Thayer's brand, alcohol free with Aloe)

1 pinch Himalayan Salt

Next, add the following Essential Oils:

7 drops Purification

7 drops Thieves

5 drops Lavender

3 drops Cedarwood

2 drops Lemongrass

Cap, and label! Bring with you on local outings, hiking, or camping. We never leave home without this stuff!

*Purchase the oils to make this blend here.

DIY Herbal Spray:

I have not tried this... yet!

But, if you don't have essential oils on hand, you can still make your own spray using fresh herbs! You will need:

One organic lemon, freshly sliced.

A few sprigs of various herbs like rosemary, lemongrass, and/or lavender.

1 qt water.

Bring all this to a boil, steep the herbs, and let it cool overnight.

Strain, and pour into a spray bottle.

Use it as a spritzer before heading outdoors to ward off insects!

*For summer skin irritations or bug bites that DO happen: Check out my DIY Skin Soothe Spray HERE!

Many natural products are on the market as well. This includes essential oil based sprays, and topical treatments. I have heard great things about Wondercide products, which are great for your pets, and your entire family with their line of pest control products for dogs, cats, your home and yard. You can view their full line of products and purchase here.

Various herbal remedies are also available for use internally to protect and support the immune system, and kill off any invading parasites, naturally.

And of course:

Nothing is 100% fool proof! If you do find a tick attached to your pet, it needs to be removed safely!

*Purchase this 3 pack of tick removers here.

Your Yard!!

Keeping your yard in shape and mowed is important to prevent infestations of fleas and ticks. They LOVE tall grasses!

Adding a few plants nearby can also help ward off the enemy!

Plus, you can harvest them for cooking, making calming tea, herbal sprays, lotions and even tinctures!

Adding/ allowing beneficial critters into your yard can also keep tick populations down.

There are also some great essential oil-based yard & home sprays to use for various indoor and outdoor pesky critters.

Remember, that overall health, and a strong immune system is the best defense! Parasites can't win against a strong immune system, it is only when health is compromised that they can take hold.

If you do still use conventional products, please take a break in the winter! And do your research on the product you decide to use.

Over time, if these harsh chemical pesticides are given consistently over a number of years, the medication can continually build up in their system making reactions, toxicity and other dangerous side effects more likely to occur.

Bottom line: Use caution with any product you buy, as even the 'natural' ones can be quite harmful!

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