Flea Spray

Published Categorized as About Fleas, Cat Flea Treatments, Dog Flea Treatments

Flea sprays are used in the prevention and treatment of flea infestation. Traditional flea sprays designed to be applied directly to your pet are not as popular nowadays. Most of these sprays only kill adult fleas, which is only one step in the life cycle of the flea. Pyrethrin-based flea sprays are effective in killing adult fleas, but they must be used twice weekly. Permethrin-based flea sprays, which contain a stronger form of pyrethrin, are toxic to cats and must never be used on cats. Today, spot-on treatments are the new method of choice for flea prevention and treatment. Popular choices include Frontline Plus, Advantage, Frontline Topspot and Revolution. Sprays are still very effective, however, in combatting fleas both inside and outside the home.

Flea Spray_fleacures


Permethrin-based flea sprays, which contain a stronger form of pyrethrin, are toxic to cats and must never be used on cats.

It is important to first understand the different phases of the flea life cycle to ensure you are using the correct products in the correct order. Check out our article on the flea life cycle.

Sprays work to disrupt different parts of the life cycle. Adulticides kill adult fleas, while Insect Growth Regulators (IGRs) prevent flea eggs from hatching and larvae from developing into adults. IGRs stop the life cycle before the reproduction phase, which is the most important part of the cycle to interrupt in the eradication process. The active protein in IGRs is usually pyriproxyfen or methoprene.

Treatment (both in the home and outdoors)

It is crucial to treat your pet and other areas in the same time frame because fleas reproduce so quickly. Start by treating your pet and then spraying other indoor and outdoor areas. Vacuum before spraying the inside of your house to effectively remove a large number of flea eggs, larvae and pupae. Be sure to vacuum under rugs, floors, carpets, furniture and pet beds, as well as around baseboards, and dispose of the contents of the vacuum immediately afterwards. The vibrations caused by vacuuming will signal fleas to emerge from their cocoons. Because cocoons are water-resistant, sprays will be ineffective against fleas still inside cocoons. It is recommended that you avoid vacuuming for two weeks after treating your house with sprays because the sprays have some residual effect. After vacuuming, spray every single area in the house that your pet has come into contact with. This includes carpets, curtains, floors, rugs, furniture and anywhere your pet sleeps. Be sure to spray baseboards and underneath rugs, furniture and beds because fleas like to hide in dark places.

Flea Spray_fleacures

You can use the same spray that you used inside your house to also spray outside in your yard and garden, where fleas also thrive. The same precautions should be taken, such as spraying anywhere your pet sleeps, under any furniture and in dark areas. Be sure to also thoroughly spray any areas with sand or gravel. Try to spray either early in the morning or later in the evening for best results.

Natural Flea Sprays

There are various natural flea spray concoctions recommended for treating fleas, but you must be very careful if you go down this route, as some ingredients might be toxic to your pets. Also, some methods claim to rid your pet of adult fleas – but remember, you still need to interrupt the life cycle before reproduction!

Pyrethrin is a neurotoxin that attacks the nervous system of all insects and is derived from flower heads of Old World chrysanthemums, such as Chrysanthemum cinerariifolium. It is used as an insecticide, but also acts as an insect repellant in lower concentrations.


It is not recommended to use these sprays on cats because some essential oils are toxic to cats and their skin is more sensitive than that of dogs.

One of the most popular natural flea remedies is the use of essential oils in homemade sprays, including: eucalyptus, tea tree, lemongrass, pine, cedarwood, peppermint, lemon, lavender, orange, melrose, purification, palo santo and citronella essential oils. The scents in the oils reportedly turn off fleas, preventing them from infesting your pet. It is suggested that you spray both your pet and the pet’s bedding. It is not recommended to use these sprays on cats because some essential oils are toxic to cats and their skin is more sensitive than that of dogs.

To see some of the most popular flea sprays, check out our article on the best flea sprays

Frequently Asked Questions

How Much Does Flea Spray Cost?

The average price of commercial flea sprays for use inside and outside the home range between $20.00 and $30.00. Professional flea extermination usually costs between $100 and $300. However, the need to eradicate your life and your pet’s life of fleas well outweighs the cost of any treatment!

Does Flea Spray Work?

Flea sprays for use inside and outside the home do work, but you need to make sure you target both adult fleas and developing eggs and larvae, as described above. To do this, use a combination of sprays that include adulticides and IGRs.

Is Flea Spray Safe for Pets?

All pets should be removed from the home while you are treating it with sprays. Everyone (pets and humans) should remain outside the home for about two hours after spraying, which is usually how long it takes for the spray to dry. Organophosphates and carbamares are two common synthetic pesticides found in flea sprays. They cause convulsions, nausea and respiratory arrest in host animals (pets and humans), as well as insects, which is why they are so efficient at ridding your home of fleas.

Does Flea Spray Kill Eggs?

Flea sprays do not directly kill flea eggs. As mentioned above, IGRs prevent fleas eggs from hatching and larvae from developing into adults. For example, the IGR benzoyl phenyl urea lufenuron acts as a chitin synthesis inhibitor. Chitin makes up 25-50% of a flea’s exoskeleton and is required for strength and integrity. This IGR prevents the egg tooth (a structure made of chitin) from developing, which prevents fleas from escaping the eggs. It also causes larvae to die because they are unable to form chitin. The IGR does not kill adult fleas, but it is transferred to ovaries and eggs if an adult female ingests the substance.

What has your experience been with flea sprays? Have any brands worked particularly well? Let us know by leaving a comment below!

Leave a comment

Your email address will not be published. Required fields are marked *