Using essential oils for fleas is a very effective remedy when your pet has come in contact with these pesky insects, as the oils have anti-inflammatory, antiseptic, anti-parasitic, and analgesic properties. Fleas are small, annoying insects that parasitically live off the blood of their animal hosts.
Flea Bites on Dogs & Cats
There are more than 2,500 different species of fleas that have been identified around the world, all of which belong to the Siphonaptera order. When they attack the fur or feathers of an animal host, they burrow down next to the skin and their sharp mouth organs pierce the skin to suck out the animals’ blood. 
Fleas reproduce extremely quickly and also have specialized legs that allow them to leap huge distances onto or off the hosts. For people with domesticated pets, such as cats and dogs, fleas can be an irritating problem that is difficult to eliminate once they have come into your home. Fleas may also bite humans, even spreading disease in some parts of the world.
When these fleas bite your dog, cat or even you, the bites are very irritating, which is why one of the most common symptoms of fleas is itchiness, and the urge to scratch. They can form red welts and are prone to secondary infections, particularly if animals or people scratch the sores. Hives, blisters and other forms of rash may appear near or on the site of a bite, even if you no longer can see the insect.
While fleas tend to live on animal hosts, they are more likely to bite and irritate human hosts before leaping off to find easier prey or hide in bedding, floorboards, or clothing. Many people turn to pesticides to eliminate fleas, but this is dangerous to use on or around your pets (and your own skin), which is why using essential oils for fleas is such a popular strategy. 
List of Best Essential Oils for Fleas
The most effective essential oils for fleas include pennyroyal, cedar, lemon, lavender, lemongrass, cardamom, peppermint, basil, rosemary, and helichrysum oils. Let’s take a look at them in detail below.
Cedar oil is one of the best oils for eliminating fleas, as it will not only repel these pesky insects but actually kill them. It is also one of the best options for cleaning your home after fleas were brought in by a pet. It is only to be used in diluted form.  
How to Use: You can add this oil to a room as a cleanser for your whole home, but when using this topically on your pets, be very conservative, using only a few drops. Ensure that the cedar oil variety you choose is safe for use on pets.
The active ingredients in lemongrass oil act as an insect repellent, as the aroma is very unpleasant for fleas. It won’t kill fleas by its topical application but it can convince fleas to leave a pet host and stay away from your house.  
How to Use: One of the most popular and refreshing uses of this oil is in a diffuser, given the pleasant aroma. For topical use on an animal, simply dilute the oil in a carrier oil, such as coconut oil, and gently spray or massage your pets with the oil, before giving them a proper bath. 
This oil isn’t known as an effective repellent but for the irritation and inflammation that can often accompany flea bites, using this oil on your pet can stimulate blood flow, speed the healing process, and provide some pain relief.  
How to Use: Don’t use peppermint oil on small dogs but on larger animals, lavender oil can be rubbed in an undiluted form on the site of a flea bite. Simply watch where your dog is scratching and then apply the oil to soothe the discomfort.
Another insect-repellent essential oil on the market, pennyroyal oil can be used to keep insects away from your home, even when using a small amount. However, this oil can be highly irritating and even toxic, so use caution!  
How to Use: This oil can be sprinkled or sprayed around your home, particularly in areas where fleas would like to live. Don’t allow your pets to lick or consume this oil, nor should you apply this to your skin or the fur of your pet, as it is strictly considered a repellent. 
Not only will helichrysum oil eliminate fleas on your pet’s body but it will also help to speed the healing process and provide pain relief, due to its analgesic properties. It will also help moisturize your animal’s skin in those irritated areas.  
How to Use: Dilute 5-6 drops of this oil in a carrier oil and then topically apply to the areas on your pet that are most inflamed and itchy. Re-apply once a day until the itching behavior stops.
This oil is well known as an insect repellent, which is why so many cat and dog owners keep it on hand. The powerful active ingredients in lemon oil, combined with the strong smell, can keep fleas away from your home and the “hot spots” where they like to live. 
How to Use – Sprinkle a few drops of lemon oil on your animal’s bedding or areas of the home where they like to spend time. This will eliminate fleas from that area and help to prevent infestations. 
With its antibacterial effects and strong anti-inflammatory abilities, using cardamom oil can help to protect your animal from any secondary infections, while also soothing pain and discomfort associated with flea bites. 
How to Use: Dilute this oil with jojoba oil and then gently massage it into the areas of your pet’s body that is itching them the most. You can also apply a diluted amount to your own skin if you are suffering flea bites. 
Rosemary oil contains many impressive active ingredients that can help heal flea bites. It will also cause them to flee the body of your pet. However, do not use this oil on cats, as it can be toxic to our feline friends. 
How to Use: When you give your dog a bath, put 5-8 drops of this oil and scrub the animal thoroughly. This will help rid your dog of the infestation, while also speeding the healing process of the bites and preventing any other infections.
Word of Caution: If you choose to use essential oils for fleas, there are a few things you should take into consideration, to ensure the health and safety of your pets.
- Essential oils are highly concentrated and may cause irritation or inflammation on the skin of your pets.
- Cats and dogs are known to lick at wounds or irritated areas; ingesting certain essential oils can be toxic or cause gastrointestinal distress in animals, so either have your pet wear a cone or only use mild oils.
- There are also certain risks of using essential oils to pregnant women and children, so if you are using this oil to eliminate a flea infestation in your home, pay close attention to the type of oil you are using, and what its possible side effects can be.
We would also suggest that it is best to speak with a veterinarian before using essential oils for fleas on your pets.