Summary
Dawn dish soap does kill fleas. It works by reducing the surface tension of water. Fleas sink and drown instead of remaining on the water’s surface. The dish detergent also prevents insects’ waxy cuticles from repelling water. As a result, water can enter their respiratory system to suffocate them.
Details
Adding dish soap to water is a common way to drown fleas. For instance, placing a plate of soapy water beneath a lamp works as a flea trap. Or fleas can be drowned in a bowl of soapy water after being combed off a pet.
Dawn Works as a Surfactant
Forcing Fleas to Sink
Dawn contains surfactants, which are compounds that lower the surface tension of water. Fleas will sink and drown when a couple drops of Dawn are added to water. Without a surfactant, fleas won’t break the water’s surface tension. This is because of their small size and water-repellent layer of wax. They’ll stay on the surface, flailing around and possibly escaping. Fleas can survive up to seven days in water, and up to 24 hours when submerged.
Allowing Water into the Respiratory System
Insects don’t drown easily. Their respiratory systems are resistant to oxygen deprivation. Fleas, and other insects, are covered in a layer of wax that repels water and makes them non-wettable (hydrophobic). The waxy layer extends into the trachea, preventing water from entering their respiratory systems.
Dawn’s surfactant properties make fleas more wettable. The waxy cuticle won’t repel water, and thus it’ll enter into their respiratory systems. The fleas drown as the water displaces air. In addition, the soap creates suds which may physically block the spiracles (respiratory entries), preventing the exchange of air and causing suffocation.
Bathing Pets with Dawn
Dawn is sometimes used as an alternative to flea shampoos. The detergent drowns fleas on pets by the same mode of action as previously mentioned. However, it’s important to keep in mind that dish soap isn’t made for animals. Dawn is much harsher than pet shampoos. It’ll remove an animal’s natural protective oils, and their skin can get extremely dry and irritated. Even with gentle, pH balanced pet shampoos, it’s advised not to bathe pets more than once a month. Avoid using Dawn on animals with skin infections.
Insecticidal Effect of Soap
Soapy water has been used as an insecticide for thousands of years. It’s believed that soaps break down cell membranes and remove the wax from insect cuticles. As a result, insects can’t retain water and quickly desiccate. Soaps may also interfere with the cellular metabolism of insects, working as growth regulators. However, glycerin soaps show little to no effect on fleas.
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My dog has been itching excessively what should I do
The first step is to check to see if your dog has fleas, or if it’s some other condition. View our How to get check for fleas section on the home page.
Does generic “Dawn” work as well as the real stuff for killing fleas?
I’d assume so. All dish soaps should have surfactants in them.
Re Puppy Flea Bath- Does it matter which Dawn soap one uses to kill fleas on dogs?
It shouldn’t matter which kind of Dawn you use. They should all contain a surfactant ingredient.
My cat has a sensitive skin condition where he’s allergic to the flea saliva therefore causing a massive outbreak of irritation to just one bite with some severe flea bites, should I use Dawn, or should I use a flea shampoo with natural ingredients?
I’m not a vet, so I can’t give any specific advice. However, I’d opt for a flea shampoo with natural ingredients. Dawn can be harsh on the skin, removing the skin’s natural oils and causing dryness and more irritation.
I did a flea dip on my dog approx 3 to 4 days ago but he still has fleas, I was told at vets that if I wash him in dawn dish soap It would strip away the dip and I could put his first shield on. Is that correct?
Yes, the Dawn dish soap will remove the flea dip. It’s not a good idea to wash the dog after treatment has been applied, especially with Dawn. Flea dip/drops work by incorporating into the dog’s natural oils, which then spread over the dog’s hair and skin. The Dawn will remove the oil and thus the treatment.
It’s not uncommon to find fleas on pets after treatment has been applied. The treatment should kill the adult fleas on the dog. However, 95-99% of fleas are eggs, larvae and pupae living in the environment. As these immature stages mature into adults, they’ll jump onto the dog. So you are likely seeing new fleas on the dog. These fleas should succumb to the treatment within 12 hours, dying before they can reproduce.
Give it more time before you deem the flea dip ineffective and look for other control options. If you want to remove the fleas you find on your dog, using a flea comb would be a better option than Dawn.
Are they bitting me or do I have the creep claws from see them on the dog.
If they bit you, then you would know. The bite reaction is similar to a mosquito bite and would be quite itchy the day after the bite.
Hi all, it’s been a horrible flea season here in the Poconos. We have 3 beautiful little cats who are indoor cats. Yet, they caught fleas. Reading your comments I want to add 2 things we’ve learned. The blue Dawn is the gentlest and recommended. The lavender Dawn actually repels fleas.
Can Dawn dish soap be used around the house to kill fleas too? What would be the best way to use Dawn dish soap for around the house flea killing?
What is the best way to use Dawn dish soap as a flea bath for your pet? Should I start at the head and wash down the body to tail for best results?
Should I use non concentrated soap or concentrated soap?
Thank you!
Lilith, unfortunately, I don’t have good answers to these questions.
I suppose Dawn could be used around the home, but I don’t know how effective it would be. Most fleas develop at the base of carpets (or cracks in hard floors). Using Dawn on carpets probably isn’t a good idea, as it will be extremely sudsy and difficult to remove. I’m guessing there’s a good reason why there are shampoos specifically designed for carpets. And even with vacuuming, wet carpet cleaning, and steam cleaning, you won’t be able to kill 100% of the fleas. It seem to me like it could cause more problems than it will solve, but I don’t know for certain.
Washing from head to tail makes sense to me, as it won’t allow the fleas to escape and hide anywhere.
I don’t think it matters whether it is concentrated or non-concentrated. In the article I mainly reference non-concentrated Dawn though. The main thing is that it should be a detergent with surfactant properties (which most dish washing soaps should be).
Having used Dawn and speaking to others for tips, I was told that fleas will quickly try to escape when threatened with Dawn, so to prevent this, start by making a ring of soap around the face and ears (careful to avoid the eyes and mouth) and also around their privates, as these are the best spots to hide. I have to admit, while bathing our pets, the fleas did immediately try to go in their ears, eyes, nose and mouth…poor things. I found the easiest way to avoid soap where it shouldn’t be, I dabbed it on with paper toweling dipped in the soap and no water so that it wouldn’t drip in their eyes, etc.. It made a nice barrier. After you have the barrier in place, continue to wash with the Dawn and water solution. I also found a site that suggested mixing white vinegar into the mix, and it did seem to be even more effective at killing the fleas, though it doesn’t smell the greatest. Best of luck!
How long does it take frontline flea medicine to kill fleas on the dog
The adulticide in Frontline is fipronil. From what I’ve read, the fipronil should quickly kill any exposed fleas. Most should die within a few hours. However, in some cases, it may take slightly longer (up to 24 hours). Still, this is a fast enough death to prevent new adults from laying eggs.
Someone must be getting a kick-back from Dawn. The truth is that any soap will do. Dishwashing soap happens to be most effective since it creates the most suds.
It was written on Dawn because that is what most people are searching, and I wanted them to find this page easiest. It is the surfactant ingredient that does the work in detergents, as it causes the fleas to sink.
How does Dawn dishwashing soap work on the flea eggs?
See our article on Do flea eggs drown in water, which includes that information.
Do flea bites leave scabs on cats and dog? Is so should I use tweezers to remove the scales? Can a fest of grass fleas on a cat kill a cat or? Dog?? Does it thin out cats hair?? I tried apple cider vinegar and water but done no good!! And about 4 different product spray but nothing seems to work!!! I bought severn to put in the yard it dosn’t. Appear that that works either!! I have 6 cats and one dog and there all getting a dawn bath today!!! . Thank you❤️ sue
Flea bites can leave scabs, particularly if the animal overly grooms and causes self-harm. This typically happens to those with flea allergy dermatitis. The over-grooming can also cause hair loss. I don’t see the benefit of removing the scabs with tweezers. I would think it would be best to let the wounds heal naturally, but you may want to consult a physician about that. There have been cases of animals dying from heavy infestations causing too much blood loss and anemia. This isn’t common with pets though. Typically it happens to young animals that have huge numbers of fleas and aren’t been treated.
I have always preferred using dawn instead of flea treatments if it is a mild case because some treatments can make your pet sick. I had a terrible infestation once where I moved and I places a few trays of dawn dish soap and water around the house which did wonders for the ones that would jump when you walked by, I would also bath my dogs with dawn followed by a moisturizing conditioner to make their hair soft, then when I would be using the flea comb I will have a dish of dawn and water waiting so I can dip the comb and be able to catch them easier and then dip them in the dish and you know they are dying when they start squirming in the water which doesnt take long.