Skip to Content

Diatomaceous Earth for Fleas on Dogs? 5 Reasons to Reconsider

Diatomaceous earth for dogs isn’t inherently bad for your dog. Unfortunately, it’s a slow and inefficient method of getting rid of fleas. Why? Because fleas remain dormant in pupae (egg) stage. They are resistant to all flea control methods until they become adults. 

As you’ll see in this post, diatomaceous earth is an effective insecticide for around the house, but not the best idea when you’re trying to get rid of fleas. The longer it takes to get rid of those fleas, the more uncomfortable your dog is going to be. 

Meanwhile, those fleas are spreading to other pets and nesting in your furniture. 

The idea of applying a topical flea treatment on your dog (or administering an oral medication) doesn’t sit well with many dog parents. The reality is, however, that these products are safe when used on the advice of a licensed veterinarian.

Diatomaceous earth takes forever to get rid of fleas

What Is Diatomaceous Earth for Dogs?

Diatomaceous earth is a powdered substance and a unique type of sand that consists of fossilized algae. It is made from the fossilized remains of tiny, aquatic organisms called diatoms. The size of each diatom is about the width of a human hair.

It contains silica and traces of other natural minerals that are broken down into a fine powder. Although it doesn’t look like it, the powdery substance is actually quite sharp for insects.

 How Does Diatomaceous Earth Kill Fleas?

Diatomaceous Earth functions by drying out the fleas that lead to its death. Many insects, including fleas,have hard outer bodies or shells called the exoskeleton. 

When fleas touch Diatomaceous Earth, it damages their exoskeletons and clings to their bodies. Diatomaceous Earth absorbs the moisture from fleas’ bodies until they dry up and perish.

Adult fleas begin to die as quickly as four hours after contact with Diatomaceous Earth. It might kill some flea larvae but is not effective against flea eggs or pupae.

Types of Diatomaceous Earth

There are two main kinds of Diatomaceous Earth available for purchase:

Food Grade and Filter Grade. 

Food grade: This type of Diatomaceous Earth contains 0.5–2% crystalline silica. It is used as an insecticide and an anti-caking agent. 

Filter grade: This type of Diatomaceous Earth contains upwards of 60% crystalline silica. It is inedible, toxic to mammals, and has many industrial uses.

Be sure to get the food grade Diatomaceous Earth. Filter grade form is not safe for use in your home.

How to Use Diatomaceous Earth to Control Fleas

Diatomaceous Earth is easy to use and looks like a plain white powder. It is used as flea control to minimize fleas in your pet’s environment and isn’t harmful should your pet accidentally swallow a small amount.

Unfortunately, it’s a messy process that is going to require several applications over a series of weeks. A one-time application may not harm your dog but, over time, the drying effects of diatomaceous earth can cause serious skin issues in your dog.

Diatomaceous earth is certainly not recommended for dogs with allergies or skin issues of any kind.

Directions for Use:

  • Always use food-grade diatomaceous earth rather than filter grade variety.
  • When applying DE powder, wear gloves and a face mask. This will protect yourself from the drying effects of this product.
  • Pour a generous amount of Diatomaceous Earth all over your home, including carpets, rugs, and floors.
  • When applying on your dog, try to apply close to the skin. This will eliminate the dust cloud.
  • You can use Diatomaceous Earth outdoors as well but will need a generous amount. The results will depend on weather conditions.
  • Allow the diatomaceous earth to remain in place for a prolonged period. 
  • Repeat the application as necessary.
  • Reapplication will be necessary if your dog gets wet.

You may see minimal results; however, the risk of skin and lung irritation remain high.

Diatomaceous earth for fleas on dogs is not recommended by most veterinarians.

Side-Effects of Diatomaceous Earth for Flea Prevention 

The use of Diatomaceous Earth for flea prevention on dogs does have some downsides. It is safe to use on pet bedding. Prolonged exposure to Diatomaceous Earth can have substantial side effects on pets as well as humans. 

The following are the top 5 reasons to reconsider using diatomaceous earth on dogs for fleas:

Potential Lung Damage

This product consists of a very fine powder-like substance. It only works when it is totally dry and when it hits the air, tiny particles become airborne. Some of the product will get where you want it to go. However, a portion of it will also get inhaled into the lungs which can result in irritation, coughing, and – over time – lung damage.

Slow and Ineffective

Do not expect immediate results while using Diatomaceous Earth. The fleas have to come into direct and prolonged contact with Diatomaceous Earth to have an effect.

Eye Irritation

As mentioned above, this powered substance easily becomes airborne and is inhaled into the lungs. As it floats through the air it’s inevitably going to find it’s way into your eyes and into the eyes of your dog. This will create pain, redness, and tearing.

If this happens, the eye needs to be flushed with clean water immediately. Flushing the eye is the only way to safely remove it. Do not rub your eye as this can cause micro-scratches.

Skin Irritation & Infection

Dogs with allergies, dry skin, or sensitive skin will find diatomaceous earth uncomfortable. The nature of this product is to dry and break through the outer barrier of insect shells. When applied to the skin it has the same drying effect.

Dogs with dermatitis, allergies, open wounds, cuts, etc., should not be exposed to diatomaceous earth.

If the above information hasn’t dissuaded you from using DE on your dog, keep reading. The following are the top 5 reasons to reconsider diatomaceous earth for fleas on dogs.

1. Risk of Skin Infection and Irritation

Many expert vets do not recommend the use of Diatomaceous Earth for dogs. It is very absorbent, and this can contribute to dry skin. Prolonged exposure to DE can have a slight drying effect on your dog’s skin.

A qualified vet and consultant in Fort Collins, Colorado, Dr. Jennifer Coates explains about use of DE on pets. He says: “Do not apply diatomaceous earth directly to your pet. It is not effective for flea control when used in this manner and could potentially result in lung damage if inhaled.” 

Dr. Susan Jeffrey, a vet at Truesdell Animal Care Hospital in Madison, Wisconsin clarifies that “Aside from possible respiratory risks, I could see it as being a hazard to the gastrointestinal tract.” 

2. Selecting the Correct Amount of Diatomaceous Earth is Very Difficult

It is difficult to apply the correct dose of DE without the advice of an expert. Many pet parents either misapply or over-apply it.

 Diatomaceous Earth Only Kills Adult Fleas

One limitation of using diatomaceous earth to control fleas is that it doesn’t prevent flea reproduction. It might kill adult fleas and some flea larvae as well but it is not effective against flea eggs or pupae. 

As the flea eggs hatch, more fleas will appear on your dog’s fur. Thus, DE can never wipe out the complete population of fleas from your dog.

Pet Parent Tip: Numerous factors might contribute to the flea problem. You must consult an expert or a vet. Your vet is the best person to talk to about any type of flea prevention method. 

3. Increases the Risk of Secondary Conditions

The reason for this is because of the long time it takes DE to work. Frequent applications over time may eventually diminish the flea problem; however, the longer your dog has fleas the greater the chance of swallowing one and developing tapeworms.

4. Expensive in the Long Run

Diatomaceous earth can be costly if you need to use it frequently. If it, or your dog’s fur, gets wet, it needs to be reapplied. Depending on the size of the dog, this could result in frequent trips to the store.

5. You Have Better Things to Do

When you consider the potential risks to you and your dog’s health compared to the overall safety record of flea, parasite, and tick control medications, you’re better off sticking with the tried and true.

You will spend a fair bit of time trying to eliminate fleas from your dog when all you really need to do is buy a veterinarian-approved product, apply a quick drop to the skin, and forget about it for a month or more.

If you’re worried about the side-effects of veterinarian approved products like Advantage, Frontline, Seresto, Nexgard, etc., talk to your veterinarian about the risks. Millions of dogs are protected by these products without major side-effects.k

At the end of the day, the risk of fleas, ticks, and worms are a much greater threat to your dog’s health. Why spend a lot of time using unproven methods of flea removal?

Alternatives to Diatomaceous Earth for dogs

The best alternatives to diatomaceous earth are those that are recommended by your veterinarian. Keep in mind that the doctor know your pet’s health history and, because of this, will be able to recommend the safest product for your dog.

Some of the most commonly used products for flea and tick prevention include the following:

NexGard Chewables






K9 Advantix II


It’s understandable why you might want to try all-natural alternatives to flea control for your dog. The reality, however, is that the longer it takes to get rid of a flea infestation, the greater the risk to your dog, your home, and other pets in the house.

It’s easy to find examples of people online who say their dog had horrible side-effects of flea prevention medication. There are always risks, but these can be easily mitigated by continuing to see the same veterinarian who will know your dog’s health history.

At the end of the day, you have to be comfortable with what you give your dog. Remember that the online stories you hear don’t often take the whole story into consideration. Still worried? Talk to the vet!


Merck Vet Manual

Did you find this blog useful? Feel free to share your thoughts in the comments. We would be happy to hear from you

Thank you for reading this post!

I want to take a moment to thank you for reading this post. I hope you found it useful and informative. If so, could you take a second to spread doggy love through social media?

You'll find the buttons at the top of this post and at the bottom of the post. might have noticed a little heart at the bottom left of your screen? Give it a click if you want to bookmark this page for future reference.