What are cat allergies?

A girl sneezing infront of cat

Your eyes itch, you start sneezing and your nose runs after a few short minutes in the company of a cat. That could be cat allergies. Spending time with someone who has a cat may trigger a reaction too. Or there might be no obvious cat connection at all. You keep getting allergy symptoms indoors and have no idea why. Read on to find out about cat allergies, what causes the symptoms and ways to manage your condition.

What causes cat allergies?

In the US as many as three in 10 people with allergies have allergic reactions to cats and dogs. Dog ownership is higher at 38% of US households versus 25% for cats. Yet cat allergies are about twice as common. People often think it’s the cat’s fur that causes allergy symptoms. In fact it's proteins in their saliva, urine, sebaceous glands and dander (tiny particles of shed skin) – even their tears.

Why are cat allergies more common than dog allergies?

Cat allergens are very good at triggering an allergic reaction. And there are a lot of them about. Of the airborne indoor allergens you can breathe in only dust mite particles are more common.

Dogs tend not to care too much about personal hygiene. Cats, on the other hand, spend almost a quarter of the day grooming themselves to get rid of fleas and dead hair, and to cool themselves down. Their saliva contains one of the main cat allergens. It dries on their fur and turns into a super fine flying dust. Cat dander also carries allergens from saliva and skin oils. It’s smaller than other pet dander, as well as pollen, mold and dust mite waste. These microscopic particles spread whenever the cat moults or grooms itself.

Did you Know...?

  • There are over 58m cats in the US and 1 in every 4 households has one
  • Scientists have found 10 different cat allergens…so far
  • The main cat allergen is Fel d 1 after the Latin for cat Felis domesticus
  • Cats produce more allergens on their heads than their chests
  • It can take up to 30 weeks after a cat moves out before allergen levels drop to match cat-free homes (that is, still with some traces)

Where do cat allergies strike?

The short answer is almost anywhere indoors. A quarter of all households in the US own a cat yet two separate studies found cat allergens in over 99% of homes. Pet allergens are sticky and that applies particularly to cats. The tiny invisible traces cling to walls, furniture, even clothes. People spread them as they go about their day-to-day lives. That could be sitting on a bus, at work or school, watching a movie or at the mall. That’s how cat allergies can strike even in places where cats are definitely not allowed.

How do cat allergies work?

Pet allergy starts in your immune system. It’s the immune system’s job to protect you from bacteria, viruses, fungi and parasites. But sometimes it overreacts. With cat allergies your immune system identifies the normally harmless saliva, urine or dander as a threat. It produces antibodies called Immunoglobulin E (IgE). These trigger the release of chemicals including histamine to get rid of the intruder. And you get allergy symptoms.

What are the symptoms of cat allergies?

Breathing in cat allergens causes inflammation in the lining of your nose. The condition is called perennial or persistent allergic rhinitis; as opposed to seasonal allergic rhinitis which is hay fever caused by breathing in pollen. If you’re allergic to cats the symptoms can feel a lot like a cold and may include:

  • Stuffy nose
  • Runny nose
  • Sneezing
  • Itchy nose
  • Itchy, red watery eyes
Young woman holding a small dog that might be causing her allergy symptoms
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But you may feel different from someone else you know with cat allergies. Poorly controlled, symptoms can have an impact on your home, work and social life. It can be hard to get a good night’s sleep with a blocked nose. That can leave you low on energy and make it a lot harder to focus at school or work. Cat allergies may even spoil a holiday.

Cat allergies: How to get a diagnosis

Finding out if you’re allergic to cats is the first step towards managing your condition. Your healthcare provider may suggest an allergy blood test or skin prick test to help identify your triggers. Be ready to give them details of what you think could be cat allergy symptoms; when, where and how badly you get them, and how often you’re in contact with a cat. Your medical history and whether allergy runs in your family are also important factors in making a diagnosis.

Allergy Immunotherapy

A man and woman hugging in blue

Do cat allergies mean…no pet cat?

Living with a cat immerses anyone living with them in allergens – whatever the breed. And homes with more than one cat tend to have higher levels of cat allergens. Sadly there’s no scientific evidence to support labelling certain dogs or cats hypoallergenic. All cats produce allergens and can cause allergies, even hairless breeds. Neither the length of their fur nor the amount of time the cat spends indoors make a difference. The only factor with some influence is gender. Tom cats seem to produce more of the main allergen than females or neutered males.

Whether you choose to have a cat is likely to depend on the severity of your allergy symptoms. And on how successful any treatment is – and continues to be because allergies do evolve over time.

How to manage cat allergies

Your healthcare provider or allergist will help you work out a treatment plan. This might mean a mixture of:

  • Avoiding triggers
  • Treating acute symptoms
  • Long term relief

10 tips for avoiding cat allergens

About 10 million pet owners in the US are allergic to their animals. If that’s you or you think it could be, here are some simple steps to try to help you enjoy life with your cat. Managing symptoms relies on minimising your exposure to allergens at home:

  • Sounds obvious but try not to hug and kiss your cat; wash your hands thoroughly after you stroke them
  • Ask someone who doesn’t have cat allergies to brush and groom your pet regularly but remember to ask them to do it outside, not indoors
  • Don’t have the litter tray in your main living space  
  • Keep cats out of your bedroom and off upholstered furniture
  • A HEPA air cleaner can help remove unwanted particles from the air in your home

These next tips are also useful if you don’t have a cat but could be bringing those sticky cat allergens home without realising it:

  • Clean your house regularly – and wear a mask while you do it as cat dander is very light and can stay in the air for 30 minutes once disturbed
  • Wipe hard surfaces with a damp cloth rather than a duster for the same reason
  • Use a vacuum with a HEPA filter to clean carpets, curtains and upholstery – it helps to lock the cat allergens safely inside the machine
  • Wash your clothes regularly because cat allergens love to get stuck on fabric and textiles
  • Tell friends, family and colleagues about your cat allergies so they can help you plan how to stay as symptom-free as possible
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Short-term relief for cat allergies

Symptom-relieving medications may be enough to stop cat allergies interfering with daily life. These could include antihistamines, corticosteroids or decongestants – or a combination of these. These allergy meds come in several forms, such as tablets, eye drops and nasal sprays, and different strengths. Many are available over the counter so ask your pharmacist for advice. Or talk to your healthcare provider about which might work better for you than others.

Long-term relief with immunotherapy

There is no cure for cat allergies but immunotherapy may offer long-term relief by targeting the underlying cause. You might know this treatment as allergy shots and it is available for cat allergies. Controlled repeated doses of your trigger reprograms your immune system to stop seeing the cat protein as a threat. This can stop or greatly reduce your allergy symptoms.

Your healthcare provider will be able to tell you if cat allergy immunotherapy is right for you and help you through the whole process.

Share your story
If you’ve read all the way to the end of this article, thank you. We’d love to know what you think. If you have any questions or would like to share your story of living with cat allergies, email us or head over to our Facebook page.


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