How to get rid of fleas on dogs and cats

12 June 2023 - 8 min read

Most cats and dogs will carry fleas at some time in their life. 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 schedule.

If you feel like you’ve tried everything to stop your cat and dog (and you!) from scratching, don’t worry. We'll explain how to break the life cycle and get rid of 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 anaemia, 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 anaemia 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 spot-on 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 arm pits and around the 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 comb 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 tail, groin area and belly

  • Excessive hair loss and skin redness can also be a sign 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 that 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 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 Kirsten'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 correct preventative product each month.

  • Use a feline-safe product for cats and a canine-safe product for dogs. This also means no splitting doses between pets and using a product as directed.

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

  • Pets in the UK should be treated monthly year round due to our very moderate temperatures.

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

  • Safe insect inhibitors to treat your home, such as Indorex spray by Virbac, 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 Kirsten.

"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 programme 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 lifecycle

Flea life cycle

The adult fleas that live on your pet only actually live for between a few days to two weeks. But the full lifecycle 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 take about one-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 emerged, they will be an adult flea. And the lifecycle begins again.

The temperature and humidity in their environment must be perfect in order for them to move through this process swiftly. The warmer it is, the quicker they’ll become adult, 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 effective flea treatment:

  • From reputable pet retailers

  • Online pet medicine retailers

  • Anti-parasite subscription boxes

  • From your vet

Flea treatments can be a spot-on 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 spot-on treatments will also kill any new fleas that mature and jump onto your pet for about a month. using these spot-ons once a month for several months can effectively break the lifecycle of fleas in your home.

How to use flea spot-on treatments

Flea treatments usually contain insecticide, and the strength of treatment you buy will vary depending on your dog’s weight.

It's important you buy the right strength of treatment to avoid your pet becoming ill, or the treatment not working.

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 you may need to dab the spot on over two or three locations along their back with some products.

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 may 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.

If your dog has fleas, you should also get them treated for worms at the same time as flea larvae can also contain the tapeworm parasite. If your dog eats the flea while grooming himself, he may become infected.

Why is my flea treatment not working?

Fleas can live for up to one year and can lay around 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 that you catch any missed eggs, fleas or larvae.

Your dog’s bed should be washed, at around 60 degrees centigrade 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 advise 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 dogs coat. This movement could make your dog feel more itchy.

  2. It can also take a while for all the fleas to die. The fleas on your dogs 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 dog could also be itching because you’ve given your dog the incorrect dose of flea treatment, so it's not working. Weigh your pet and buy the right strength product. Don’t be tempted to buy a strength that is too strong for your dog.

  5. If you’re a multi-pet household with more than one dog or cat, you need to treat everyone 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 lifecycle, and you’ll struggle to eliminate the flea 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 dog. Even one bite can cause hours of itching.

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

If your dog has FAD he may need a corticosteroid treatment or cortisone injections prescribed by your vet to relieve the uncomfortable symptoms. Additionally, the 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.

Sea water and dog fleas

Salt can dehydrate fleas, and it's thought 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 Husky, Akita and Shiba Inu are more likely to develop skin irritation after swimming in the sea, than others. 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 sea 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 can help kill the fleas. 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 it could irritate their skin and eyes.

In the TikTok videos the turmeric also died 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 effectivness.

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

Does pet insurance cover flea treatment?

Pet insurance doesn’t cover routine or preventative healthcare like treatment for fleas, ticks and worms.

However, ManyPets Flea, tick and worm plan offers treatment that can protect your pet against these parasites. You’ll get a discount on the plan and you don’t need to have an insurance policy to buy it.

illustration, flea under a magnifying glass

Keep your pet parasite free

Get your essential preventative treatments delivered to your door every month with the ManyPets Flea, Tick and Worm plan.

illustration, flea under a magnifying glass

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 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 that live on dogs, and Ctenocephalides felis that lives on cats.

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

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.