Fleas in cats

Fleas are a very common problem for cats. The Big Flea Project in 2018 found that 28% of cats in the UK were infested with fleas. Cats of any age can be affected.

If caught early, it’s easy to get rid of fleas. If left untreated, it can take longer to clear infestations, and cats can develop severe skin problems. There are products available to protect your cat against fleas if they’re used regularly.


What are fleas in cats?

Fleas are common parasites that live on the skin of cats and in the household. They are small, dark, and oval in shape.

cat flea
Image of a cat flea

How do cats get fleas?

  • Cats catch fleas through direct contact with other animals, including dogs, and even wildlife. Fleas can spread indirectly through grass, clothing, footwear, and bedding. They can jump long distances too. Indoor-only pets are also at risk.
  • Adult fleas survive by feeding on blood. This can lead to serious anaemia if there are lots of fleas. This is more common in very young and older animals.
  • Fleas can carry other diseases, such as tapeworm, that can infect our cats. Find out more about Worms in cats
  • Fleas are more common in the summer but are present all year round.
  • The lifecycle of a flea involves eggs, larvae, pupae, and adult stages. In favourable environments, it only takes 15 days from the egg to the adult stage, so they can grow quickly in numbers.
  • Adult fleas are mostly found on the skin surface of our pets. Eggs, larvae, and pupae are found in the environment, such as deep in carpets, crevices, or furnishings. They can survive for years in the right conditions.
  • Cats can develop allergies to fleas; just one bite can cause a severe skin irritation. This is called Flea Allergy Dermatitis in Cats
Fleas in cats. Image of flea lifecycle.
The lifecycle of fleas in cats

Flea infestations can be extremely difficult to get rid of. Prevention is much better than treatment. Treatment can be frustrating, expensive, and often takes several months.


Symptoms of fleas in cats

How to tell if your cat has fleas.

  • Some cats may not show any signs of fleas at all.
  • Signs of itching, scratching, biting, and licking.
  • Hair loss, especially on the back and top of the tail.
  • Skin sores, such as red spots and dry skin. These are common with flea allergies.
  • Black spots on your pet’s coat or in their bedding. This is also known as flea dirt.
  • Low energy and weakness
  • Pale gums, especially in very young and older cats. This is due to anaemia, which means a reduced amount of red blood cells in the body. This can be extremely serious, even life-threatening.
Fleas in cats. Areas of body affected by fleas.
Areas of the body affected by fleas
fleas in cats
Hair loss due to fleas


Are some cats more at risk of fleas than others?

Cats of any age, breed, or sex are at risk of fleas.

  • Fleas may be more difficult to spot in cats with longer, heavier, or darker coats.
  • Outdoor and sociable cats are more at risk of catching fleas.
  • If one of your pets catches fleas, it’s likely that all other pets in the household will also have them.


Is my family at risk of catching fleas?

  • Cat and dog fleas can bite humans, but they don’t live on our skin.
  • Flea bites on humans often appear as a red spot or scab.
  • These can become itchy and infected.
  • We recommend speaking with a pharmacist or doctor about how to treat this.


How are fleas diagnosed in cats?

The diagnosis of fleas is usually easy. It may be done at home, though it is often best to get a professional to check if you’re unsure.

  • Fleas are usually diagnosed by finding live adults or flea dirt (flea faeces) on the coat.
  • Check the thinner-haired areas, such as the inner thighs or tummy, for adult fleas. They move very quickly, so they may be difficult to spot.
  • A paper test can be used to check for flea dirt. Brush your cat using a flea comb onto a sheet of white paper or paper cloth. Flea dirt looks like small black specks. Apply a few spots of water, and they will leave red streaks on the paper.
  • Fleas may also be suspected based on the symptoms. Itching and the pattern of hair loss or skin sores can suggest fleas.
  • There are many other causes of itching in cats; it’s best to speak to a veterinarian if your cat is itchy but there are no signs of fleas. Find out other causes of Itchy cats
how to know if your cat has fleas
Brush your cats hair onto a white piece of paper
flea test cat
Flea dirt will appear as red streaks when water is added


If your cat has hair loss or skin lesions, your vet may recommend the following tests to check for other skin diseases

  • Skin scrapes, hair plucks, and a skin biopsy
  • A diet trial
  • Blood and urine tests

Vet treatment

What’s the best treatment for fleas in cats?

Treatment for fleas involves both killing the adults on your cat and eliminating any other stages in the household.

Treat all of the pets in the household with a vet-recommended product.

  • Speak to a vet before applying any products; some may be toxic to different animals. https://www.vpisglobal.com/common-poisons/
  • Make sure to use the correct product based on your pet’s weight.
  • Repeat these regularly, as advised by your vet. This is mostly every 4 weeks, but some are every 3 months.
  • Prescription medications include spot-ons and oral treatments.
  • Some over-the-counter flea products are effective at treating and preventing fleas. These come as a spot-on or collar.
  • If using a spot-on treatment, do not bathe or let your cat out in heavy rain for at least 48 hours, as this can reduce the effectiveness of the medication.
  • Flea shampoos, powders, and herbal remedies are often not effective at killing fleas. Especially as long-term solutions. They may also contain toxic substances.
  • Fleas can carry tapeworms. It’s important to treat your cat for tapeworms regularly, especially if they have fleas. There are some effective over-the-counter medications to treat tapeworms. Prescription medications are also available.


Cats that are extremely itchy, have skin rashes or have flea allergies may need prescription medication.

  • Anti-itch medications may be needed.
  • Antibiotics in tablets, injections, or topical forms for secondary skin infections.



Home treatment

How to get rid of fleas from the household

95% of fleas live in the environment, so treating the home is very important.

It can take several months to get rid of a flea infestation. The best advice is to follow the recommended guidelines and be consistent with treatments.

Treat your house and your car with a vet-recommended product against fleas

  • The environment will often need more than one treatment, as the next cycle emerges after 2-3 weeks.
  • Household sprays that kill the adult fleas and prevent egg and larvae development tend to be the most effective.

Wash all bedding and vacuum regularly

  • Hot wash (over 60℃) all bedding your cat has been in contact with and clothing that has been on the floor.
  • A dry cycle is also recommended.
  • Vacuum the whole house.

For cats with skin lesions, hair loss, or itching

  • For very itchy cats, prescription medication is often needed.
  • Use a calming shampoo or mousse for mild skin irritations.
  • Use a buster collar or pet medical suit to prevent self-trauma.
  • Skin supplements containing omega oils can be useful for irritated and itchy skin.


Tips on how to prevent fleas in cats

Prevention of fleas in cats is much easier and more cost-effective than treatment.

  • Use a recommended flea-preventative product all year round, even if your cat is indoors only. Flea products are usually applied monthly, but some products may last longer.
  • Groom and brush your cat regularly to check for anything abnormal in their fur or on the skin.
  • Vacuum regularly, and put your cat’s bedding in a hot wash cycle.
  • Use a household spray that kills fleas and their eggs; these often last 6-12 months.
  • Limit contact with stray or unknown animals who may not be on regular flea control.
  • If you have a garden, mow the grass regularly and prevent access to wild animals.


When to worry

What to do if you are worried your cat has fleas

Seek help from a vet if

  • Your cat is constantly itching or scratching.
  • Your cat has a lot of hair loss or widespread skin lesions.
  • You have a young or old cat with fleas, and they are lethargic.

Joii can help if

  • Your cat has any minor skin problems or itching.
  • Your cat has been diagnosed with fleas, and you need advice on treating the house.
  • You want to know more about flea prevention in cats and how to apply it.
  • You want to know how to check your cat for fleas.
  • You need tips on how to brush your cat.


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