Does Neem Oil Kill Fleas? Benefits And Side Effects

Sandra Tashkovska
•
May 20, 2025
Fleas are the most common external parasites in dogs. To keep them off your pets, you need to implement a year-round flea preventative product. Fleas usually cause itching, but in severe cases, they can lead to serious parasitic or skin infections.
Science moves forward so fast, but we as humans want to go back to the old conventional treatment for both us and our pets. This is because of the knowledge we have about the strong chemical formulations and the side effects we know about them. So, more and more pet parents would rather include a natural alternative for flea control.
One famous natural remedy for fleas is neem oil, which is a plant-based pesticide found in the seeds from the neem tree. Here is everything you need to know about neem oil and its potential usage in natural flea control in pets!
Understanding Neem Oil
Many people know neem oil as margosa oil, and this tree (Azadirachta indica) originates from the Indian subcontinent. The most popular usage of this oil is as a potent pesticide in organic farming. It has a yellow to brown color and has a smell like garlic or sulfur.
The active compounds in neem oil are:
- Azadirachtin: This compound disrupts the life cycle of the flea and interferes with its hormone system. This slows down the process of growth, reproduction, and feeding.
- Nimbin and Salannin: These compounds benefit animals and humans with their anti-inflammatory, antifungal, and repellent effects.
These are the main compounds of neem oil that directly help in reducing the flea number. Out of these compounds, Azadirachtin is the most active of these growth regulators and occurs at 0.2-0.4% in the seeds of the neem tree.
- Constant itching
- Skin damage
- Anemia
- Flea dirt
- Biting and gnawing
- Sore skin
- Pale gums
- Weakness
- Household infestations
How Neem Oil Affects Fleas?
Out of all the ingredients from neem oil, Azadirachtin is the most powerful as it:
- Reduces the insect feeding
- Repels fleas
- Interferes with he hormone system of fleas
- Reduces the ability of insects to grow and lay eggs
- Repels nematodes
According to the National Pesticide Information Center (NPIC), azadirachtin functions as an insect growth regulator (IGR), which prevents insects from developing properly.
According to studies, Azadirachtin is the most effective insect growth regulator from neem oil. It is a feeding deterrent and a repellent with low toxicity. This research showed the benefits of neem oil (azadirachtin) on Ctenocephalides felis in dogs and cats. In the first part of the study, dogs living in kennels were sprayed once with methanolic neem extracts containing different concentrations of azadirachtin: 200, 1000, or 2400 ppm. The flea count decreased in a dose-dependent way. It showed that the higher the concentration, the better the results. Compared to untreated dogs, flea numbers were reduced by 53% to 93% for up to 19 days.
In another test, a combination of 500 ppm azadirachtin with 500 ppm Deet and 33% citronella was used. This mix reduced flea numbers by 62% to 95% over a 20-day period. This means that deet and citronella lead to better results than azadirachtin alone, even at lower doses.
This suggests that while azadirachtin is effective on its own, its flea-killing action is improved when combined with Deet and citronella.
In summary, azadirachtin works against fleas in a dose-dependent manner, and when combined with Deet and citronella, it offers even better protection. This is especially in cats, where it kills most fleas within 24 hours and maintains strong control for about a week.
Application Methods of Neem Oil for Pets
While neem oil is safe and natural, you must use it safely and correctly to avoid serious consequences like skin irritation or toxicity.
Here are some tips from our Furlife team on how to properly give neem oil to pets:
- Use neem oil shampoos: Shampoos containing neem oil are a much safer way to protect your dog from fleas and still use this repellent. Although they might be hard to find, consult with your vet and find out what the best neem oil shampoo is for your pet.
- Commercial products: You might find lotions, balms, and spot-on treatments for your pet that contain neem oil. Follow the instructions from the manufacturer and apply neem oil to your pet.
- Dilute the neem oil (1:10): This is a very strong oil and might lead to serious issues if not applied correctly. It should always be mixed with a carrier (warm water or carrier oil like coconut oil)
- Clove oil at 16% was the most effective and safest for use on dogs' skin.
Note: Coconut oil can also be a powerful repellent for fleas and ticks! Read more about this here!
Disclaimer: To have efficient results and avoid side effects, you must properly dilute and consult with a veterinarian.
Other safety tips:
- Avoid using this oil in young puppies, kittens, pregnant animals, or severely sick animals
- DO NOT let your pet ingest neem oil
Benefits and Precautions
Here are some of the most common benefits that you should be aware of before you start using neem oil:
- Natural alternative to strong chemical treatments: Not all pets can handle strong chemical formulations well
- Anti-inflammatory properties: The active compounds of neem oil can help reduce the itching, redness, and inflammation in animals
- Soothing skin properties: Due to the anti-inflammatory properties, this oil can lead to smooth and healthy skin in animals.
- Cost-effective
- Easy to use
- Eco-friendly
Here are some common precautions for neem oil:
- Potential for skin irritation: This happens when the oil is not properly diluted. When it is too strong, it can lead to dry skin or even allergic reactions in sensitive animals.
- Strong and intolerable smell: While most pets tolerate this neem oil well, animals that are too sensitive or picky might dislike the strong garlic-like smell. They might even feel lethargic and tired after the application if the smell bothers them
So, what is our tip to avoid these side effects?
Always, but really always, do a patch test before you start using any topical treatment for your pet. Add a small diluted amount to one spot and wait a few hours to check if your pet shows any reactions. If everything seem okay, you can actively start using the neem oil.
Comparative Effectiveness
Here is one comparison of neem oil to conventional flea treatments:
Properties | Neem Oil | Conventional Treatment (chemical-containing products) |
---|---|---|
Efficacy | Repels fleas and disrupts flea growth | Kill fleas and ticks |
Speed | Gradual (can take up to several days or weeks) | Rapid (kills fleas within 12 hours) |
Duration | Needs reapplication | Long-lasting (up to 3 months) |
Composition | Chemical-free | Contains chemicals |
Safety | Safe when diluted, natural | No need to dilute |
You should prefer neem oil over the conventional treatment options in cases when your pet cannot handle the chemical-containing products or when you seek for a natural option. Pets with sensitive skin would also benefit from neem oil, but before that, you need to perform the patch test to see if this natural option is safe for your buddy.
On the other side, conventional treatments (chemical-containing products) are more beneficial when your pet is suffering from a heavy flea or tick infestation. You cannot escape these products, especially if your pet is having a severe illness due to the fleas.
Incorporating Neem Oil into a Flea Prevention Regimen
If you want, you can include neem oil daily for your pet. Here are some other tips besides incorporating neem oil to keep your pet safe:
- During regular grooming: Spray this oil over your pet’s body and enjoy the benefits
- Keep the environment clean: Vacuum frequently and wash the pet bedding. Also, try to keep your home as clean as possible.
- Use flea combs
FurLife's Natural Flea & Tick Products
Out of the many options on the market, Furlife provides a fast-acting custom formula and supports your dog’s needs. It contains natural ingredients and ensures that the dog gets everything he needs without any side effects.
According to FurLife’s customers, this is a lifesaver and even a game-changer product. It makes their daily life with a pet much easier. The ingredients from these products are made to repel, eliminate, and defend against fleas and ticks at every stage, even in your home.
Here are the available options of FurLife’s range:
Flea & Tick Collar for Dogs
This collar is waterproof and suitable for any size. It can prevent ticks, fleas, and even bugs. By ordering this collar, you can also get a free anti-flea and tick ebook, where you can read more about flea and tick prevention.
This collar works on a SmartRelease concept, where the natural essential oils distribute evenly on the dog’s neck. This protects the dogs from any dangerous diseases that might be transmitted.
Your pet can continue its water activities with a FurLife collar because it is water-resistant, and you don’t have to worry about anything. If the collar is too long, you can very easily adjust it by cutting it. This collar contains a synergistic blend of lemon eucalyptus, linaloe oil, cinnamon oil, lavender oil, and eucalyptus oil.
Flea & Tick Chews for Dogs
FurLife's innovative flea and tick chews contain a blend of natural ingredients, including garlic, brewer’s yeast, and apple cider vinegar. These ingredients have flea and tick repelling properties, but they also promote optimal skin and coat health.
They improve the signs of fleas and ticks, like excessive scratching, tick paralysis, flea dirt, and stress. They can help you prevent your dog from fleas and ticks, and all the diseases that might come along. FurLife’s chews are suitable for every breed, contain 100% natural ingredients, and effectively prevent ticks, fleas, and bugs.
Flea & Tick Pendant for Dogs
FurLife's innovative protective pendant is another great product that can help your pet deal with fleas and ticks. It is also waterproof and has 100% natural ingredients like Camphor Oil, Mulberry Oil, Citronella Oil, Lavender Oil, Lemon Oil, Peppermint Oil.
Your dog should wear the pendant only when outside or when you want your dog to be protected. The active ingredients are distributed through the air, and they are all free of chemicals. To make your pet trendy, you can choose one of the six colors available: pink, green, blue, red, black, and grey.
Flea & Tick Spray for Dogs
Lastly, FurLife's flea and tick spray has with dual-action formula that provides protection for both your pets and your home environment with its powerful botanical blend of Cedarwood Oil, Spearmint Oil, and Sesame Oil.
One bottle of this product will last you typically 1-2 months; it depends on the number of pets being treated, the size of the pet, and the frequency of use.
Final Thought: Does Neem Oil Kill Fleas?
The Internet is flooded with information about natural options for flea and tick control in pets. Neem oil is one of the natural remedies that works for dogs and is safe.
However, if your pet suffers from a serious flea infestation and has serious skin problems, we would recommend that you consult a vet and find some of Furlife’s products. These products are safe, and you can find the form of the product that would most suit your pet’s needs.
What is your opinion on natural remedies for pets? Have you tried neem oil, and what was your experience if you did? Let us know in the comments below!