Flea allergy in cats

Photo of cat on white background

Overview

Fleas are an everyday hazard of owning pets, regular flea treatment is essential to keep our pets (and homes) flea-free.

Most cats find fleas itchy and irritating but for some they are a much bigger problem because they are allergic to the bites. A cat that is allergic to flea bites will have a skin reaction every time they’re bitten which causes intense itching and inflammation of the skin; similar to a person who is allergic to mosquitoes.

A poorly managed flea allergy is likely to cause severe skin disease and illness.

Fortunately, with treatment from your vet and good flea control, a cat with a flea allergy can live a perfectly normal, happy life.

Flea allergic dermatitis explained

Most cats find fleas itchy and irritating but for some they are a much bigger problem because they are allergic to the bites (or more specifically the flea’s saliva). A cat that is allergic to flea bites will have a skin reaction every time they’re bitten which causes intense itching and inflammation of the skin.

They are likely to over groom, lick, bite and scratch at themselves causing their skin to become red raw and open to infection.

Flea treatment isn’t often enough to control the problem; a repellent is usually needed to prevent your cat getting bitten altogether.

Symptoms

  • Itchy skin
  • Hair loss (alopecia)
  • Over grooming
  • Lumpy skin especially around the head, neck, lower back, tummy and back legs (milliary dermatitis)
  • Red, inflamed skin
  • Raised, red patches (eosinophillic plaques) if licked excessively
  • Flea dirt in the coat (black specks)
  • Fleas – it’s easy to spot fleas on a cat with a heavy infestation, but flea allergic cats may be reacting to just an occasional bite. They also over groom themselves, so there may be no fleas for you to see.

When to contact your vet

Contact your vet for advice if you think your cat has fleas. If you suspect a flea allergy or any other skin problem, contact your vet for an appointment.

You know your cat best. If they don’t have the symptoms listed above but you are still concerned it’s always best to contact your vet.

Treatment

Eliminate fleas

  • Make sure your cat doesn’t come into contact with fleas.
  • De-flea your cat and any other pets all year round (as regularly as your vet advises).
  • Speak to your vet about flea repellents. Even if your pets are treated, fleas will still jump onto them. The flea will die once it’s taken in some of the flea treatment but the bite will still cause an allergic skin reaction.
  • Treat your house as regularly as your vet suggests (usually every 6-12 months). Remember, 95% of a flea problem is in the home, only 5% is on your pets.
  • Regular vacuuming around the house helps to remove fleas and their eggs from carpets and soft furnishings.

Steroids

  • Steroids may be used to reduce skin inflammation and the allergic reaction.
  • Steroids can be given as cream, injection or tablets.

Antibiotics

  • Antibiotics might be prescribed if your cat has developed a skin infection, this is common if your cat has been biting, chewing and scratching itself a lot.

Stop your cat over grooming

  • A buster collar, body suit or dressings may be needed until your cats medication has started to control their itch (usually within 24-48 hours). This will prevent your cat causing further damage to their skin.
Illustration showing how fleas survive in the home.

95% of a flea infestation is in the home, only 5% is on your pets.

Home care

A flea allergy can’t be cured, but it can be managed with strict flea control. You will need to make sure your home and pets are flea-free all year round.

If your cat has a ‘flare-up’, it’s important to contact your vet for an appointment to prevent them over grooming and making the problem much worse.

Outlook

Cats with a flea allergy can live a long, normal, happy life if their condition is well managed.

Prevention

You can’t prevent a flea allergy, but you can prevent symptoms developing by completely avoiding fleas.

Published: January 2019

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Written by vets and vet nurses

Illustrations by Samantha Elmhurst