How to get rid of fleas on dogs and cats

June 28, 2022 - 8 min read
Flea life cycle
Flea life cycle

Most cats and dogs will carry fleas at some point in their lives. They’re easily picked up, but once a flea infestation takes hold in your home, they can be devilishly hard to get rid of without the right treatment regimen.

If you feel like you’ve tried everything to stop your cat or dog (or yourself!) from scratching, don’t worry. We'll explain how to break the life cycle and eradicate fleas from your pets and your home for good.

Can Fleas Make a Dog Sick?

Fleas aren’t just an irritation. They can really damage your pet’s health.

  • Fleas drink blood, so a lot of fleas on an animal can cause anemia, especially in puppies and kittens

  • In extreme cases, that could even be enough to cause a heart murmur in your cat or dog. The murmur should resolve when the fleas and anemia are treated

  • If your dog or cat ingests fleas, they can be infected with tapeworm

  • If your dog or cat has flea allergy dermatitis, just one bite can cause huge discomfort, itching, redness and hair loss

Look after your pet’s health by treating for fleas as soon as you see any signs.

Many pet parents prefer to use a regular treatment like a monthly topical medication to make sure their cat or dog is continuously protected from fleas.

How Can I Tell if My Dog or Cat has Fleas?

fleaThe best places to check your dog for fleas are their armpits and around their groin area. These tend to be warm, protected areas that attract fleas.

You should also look for signs of "flea dirt," which is flea poo in your dog’s fur. For cats, the base of their tail is a good place to check for flea dirt.

It looks like black or dark brown specs, and you can check if it’s flea dirt by putting it on a wet tissue. If it’s flea dirt, it’ll leave a rusty red stain because flea dirt is basically specks of dried blood.

Another way to find fleas, larvae, or droppings is by standing your dog or cat on a white surface or towel and combing through their hair with a flea comb, nit comb, or other fine-tooth comb. The fleas should either get caught in the comb or drop to the floor.

Some other signs of fleas to look out for are:

  • Scratching, especially around the ears, base of the tail, groin area, and belly

  • Excessive hair loss and skin redness can also be signs of flea allergy dermatitis

  • You might get bites, too, especially around your ankles

It can be hard to see fleas on your dog, as they only stay on your pet while they’re feeding.

How Do Dogs Get Fleas?

Fleas can come from other animals, the outside environment, or a stay at boarding kennels.

They tend to hide in shadier areas: long grass, animal nests, and dog houses — anywhere where the conditions are suitable and where other animals may have been.

An Effective Flea Treatment Plan

"During an active infestation, a 'one and done' approach is not going to be successful," says ManyPet veterinary surgeon Dr. Kirsten Ronngren.

She says the secret to getting rid of persistent fleas is treating the whole flea life cycle.

"Because of the way the flea life cycle occurs, monthly treatment for a minimum of three months is typically needed to break this life cycle. Female fleas can produce up to 40-50 eggs in one day, and these eggs can turn into dormant life stages that can live in your carpet or other areas of your home for weeks to months before hatching into adults."

These are Dr. Ronngren's top tips for treating your pets and your home to successfully get rid of fleas:

  • All pets in the home need to be treated appropriately with their own preventative product each month.

  • Use a feline-safe product for cats and a canine-safe product for dogs. This also means using products as directed and never splitting doses between pets.

  • Not all pets respond the same to all treatments, as there are a variety on the market. Some may respond successfully to one while others may not, so remember that there are many options available if one product is not achieving success.

  • Pets in the US should be treated monthly and year-round because many areas in the US don't get cold enough to kill fleas.

  • In addition, make sure you vacuum all surfaces in your home, and wash bedding on a hot wash cycle.

  • Safe insect inhibitors to treat your home, such as PetArmor Home and Carpet Spray, are excellent options for carpeted and upholstered surfaces and will treat adult and immature stages of fleas.

"Consistency is key in these situations," says Dr. Ronngren. "Lots of people make the mistake of just killing the fleas on their pet, but they’re soon re-infested when fleas in the home hatch and mature."

That means an effective flea eradication plan should look like this:

1. Kill fleas on your pet

2. Kill or remove flea eggs and flea larvae in your home

3. Repeat so that any eggs and larvae that have been missed don’t have a chance to re-infest your pet

The Flea Life Cycle

Flea life cycle

The adult fleas that live on your pet only live for a few days to two weeks. But the full life cycle is much longer, which is why it’s so hard to break.

  1. Once a flea has had its meal of blood, it will lay eggs on your pet. The eggs don’t stay on your cat and dog, though; they fall off all around your home.

  2. It takes about 1–10 days for the eggs to hatch into larvae. These larvae feed on flea waste products — digested blood and dirt in the environment.

  3. Next, the larvae will spin themselves a cocoon or pupa, to mature in. They can take weeks, or even months, to emerge from this stage.

  4. Once they emerge, they will be adult fleas. And the life cycle begins again.

The temperature and humidity in their environment must be perfect for them to move swiftly through this process. The warmer it is, the quicker they’ll become adults, and the cooler it is, the slower the process.

The full life cycle can be several months long; that’s why you need to continuously treat your pet for several months to really break this life cycle.

Types of Flea Treatment

There are several ways to buy an effective flea treatment:

  • From reputable pet retailers

  • Online pet medicine retailers

  • Anti-parasite subscription boxes

  • From your vet

Flea treatments can be a topical medication or a tablet. Tablet treatments will only kill the fleas on your pet at the time. They don’t address the flea life cycle.

Some topical treatments will also kill any new fleas that mature and jump onto your pet for about a month. using these treatments once a month for several months can effectively break the life cycle of fleas in your home.

How to Use Topical Flea Treatments

Flea treatments usually contain an insecticide, and the strength of the treatment you buy will vary depending on your dog’s weight. It's important to buy the right strength of treatment to make sure it works and keeps your pet from becoming ill.

The treatment should be applied directly to your pet’s skin, between their shoulder blades. It spreads over their skin through a process called "dermal translocation," which just means it’s spread by the skin’s fatty layer.

Read the instructions carefully. For very large dogs, some products may require you to dab the medication over two or three locations along their back.

Once they’ve been treated, any fleas that come into contact with your pet’s skin or hair will die. They don’t need to bite your pet to be killed.

Different flea treatments may work differently and contain different ingredients. For example, (S)-methoprene and fipronil are both ingredients found in Frontline Plus. These ingredients are safe for both dogs and cats.

But permethrin, found in other dog treatments, is highly toxic to cats. It’s based on pyrethrin, found in chrysanthemums. Never use a flea treatment designed for dogs on your cat, or vice versa.

Flea treatments such as Frontline will need to be applied monthly to your dog, although this frequency may vary depending on the treatment you choose. Never be tempted to apply more frequently than stated on the packaging.

Some treatments can also treat ticks at the same time as fleas.

If your dog has fleas, you should also get them treated for worms at the same time, as flea larvae can contain the tapeworm parasite. When dogs eat fleas while grooming themselves, they may become infected.

Why Is My Flea Treatment Not Working?

Fleas can live for up to one year and can lay around 40–50 eggs a day. So even if you manage to kill the fleas, the subsequent eggs and larvae will still be around the house. In fact, this is estimated to be around 95% of the infestation, with only 5% of it being on your pet.

You should vacuum the house and any upholstery thoroughly, making sure you clean all the areas your dog or cat visits. Don’t forget to also include your car! You’ll need to repeat this regularly to ensure you catch any missed eggs, fleas, or larvae.

Your dog’s bed should be washed, at around 140 degrees Fahrenheit, to kill any fleas. Do the same with any removable coverings in the home, like sofa covers or your own bedding.

Consider spray products designed to treat your home too. Frontline advises you can also spray an insect growth regulator, as this will kill fleas and larvae.

If your pet is still itching after being treated for fleas, this could be because:

  1. Once you’ve applied a flea product such as Frontline, the fleas will move to the top of your dog's coat. This movement could make your dog feel itchy.

  2. It can also take a while for all the fleas to die. The fleas on your dog's coat can start to die after around four hours, according to a study conducted by Frontline. A separate study conducted showed that 100% of fleas had died after 12 hours.

  3. Unhatched eggs and pupae will remain on your dog and around the house, so ridding your pet and home completely of fleas can take longer.

  4. Your pet could also be itching because you’ve given them the incorrect dose of flea treatment, so it's not working. Weigh your pet and buy the right strength product. But don’t be tempted to buy one that is too strong for your dog.

  5. If you have a multi-pet household with more than one dog or cat, you need to treat every pet at the same time. Even if your other pets aren’t showing symptoms, they could still pick up stray flea eggs and larvae in the home and become infected.

Untreated pets will continue the flea life cycle, and you’ll struggle to eliminate the infestation.

Continued itching could also be caused by an allergy to the flea bite. A flea’s saliva can contain antigens, which are normally harmless. In a dog or cat with flea allergy dermatitis (FAD), these can irritate your pet. Even one bite can cause hours of itching.

FAD can cause hair loss and inflamed skin, most commonly around the base of the tail and extending down the legs.

If your dog has FAD, they may need a corticosteroid treatment or cortisone injections prescribed by your vet to relieve the uncomfortable symptoms. Additionally, excessive scratching could lead to infection, so a course of antibiotics may be required.

The best prevention for FAD is appropriate flea control treatment administered continuously.

Home Remedies for Fleas: Do They Work?

Be wary of home remedies for fleas. Many are, at best, ineffective and, at worst, could harm your pet.

Seawater and Dog Fleas

Salt can dehydrate fleas, and it's thought that a swim in the sea or a salty bath can kill the fleas on your dog. However, salt can also cause irritation and dryness on your dog’s skin. So don't overdo it.

Also, it’s thought breeds with a double coat, such as the Husky, Akita, and Shiba Inu, are more likely than others to develop skin irritation after swimming in the sea. This is because the water gets trapped inside the fur and can cause irritation.

Breeds that can handle swimming in the sea fairly well include Labrador and Chesapeake Retrievers, Portuguese Water Dogs and Irish Water Spaniels.

Always remember to rinse your dog well with fresh water after swimming to remove any salt particles.

We don’t recommend immersing your cat in water, salty or otherwise.

It’s also said that salt can be sprinkled across your carpet to dehydrate fleas and kill them. A good flea spray is likely to be less messy and more effective.

Turmeric to Kill Cat Fleas

In 2021, videos circulated on TikTok of people putting turmeric in their cat’s fur to kill fleas. Whether or not turmeric repels fleas, you should never put substances on your cat that aren’t recommended by your vet. They could ingest them as they try to groom it off, which could make them sick or irritate their skin and eyes.

In the TikTok videos, the turmeric also dyed the cats — and the floors, walls, and furniture they came into contact with — bright yellow.

Baking Soda to Kill Flea Eggs

There’s no evidence that baking soda kills fleas. It may dry out larvae and eggs when sprinkled in the environment in the same way salt does, but it’s just as messy and has no proven effectiveness.

Don’t put baking soda on your dog or cat; it’s alkaline and likely to irritate their skin.

Does Pet Insurance Cover Flea Treatment?

Pet insurance doesn’t cover routine healthcare like preventative treatment for fleas, ticks, and worms. But when you buy pet insurance with ManyPets, you’ll also have the option to purchase a wellness plan, which will reimburse you for preventative parasite treatment (along with other types of preventative care).

It should also be noted that pet insurance CAN cover illnesses that arise from parasite exposure, as long as they're not pre-existing conditions.

Can Dog Fleas Live on Humans?

If you’ve been getting flea bites, too, you might be worried that you have fleas. Although fleas prefer dogs and cats, they will also bite humans. So you may also find yourself a chosen meal.

Fleas can’t live on humans, But they can infest your home, carpet, sofa, bedding, and even clothes. This is another reason why it’s so important to flea-treat your home as well as your pet.

Can Cat Fleas Live on Dogs?

Yes, cat fleas can live on dogs.

There are two species of fleas: Ctenocephalides canis, which lives on dogs, and Ctenocephalides felis, which lives on cats.

Both types will nibble on dogs. Cat fleas are even more versatile and will bite over 50 species of animals.


Derri Dunn
Content marketer

Derri is a personal finance and insurance writer and editor. After seven years covering all things motoring and banking at GoCompare, Derri joined ManyPets in 2021 to focus on pet health. She has fostered cats and kittens for Blue Cross and Cats Protection and is owned by tabby cat Diggory and two badly behaved dogs.