Cat allergy
Itchy eyes ten minutes after sitting on a friend's sofa? Cat allergen is one of the most common indoor triggers, and it does not need a cat in the room. Our test checks your blood for IgE sensitisation to four cat proteins as part of 300 allergens and allergen components, so you can see the cat result next to dust mite, mould and pollen.
- Group
- Animals
- Also known as
- cat allergy, cat dander, Fel d 1, allergic to my cat, cat hair allergy
Where you meet it
- Homes with cats, including rooms the cat never enters
- Homes where a cat lived months ago
- Sofas, carpets, curtains and mattresses
- Offices, schools and public transport, carried on clothes
It's not the hair
The main cat allergen is a protein called Fel d 1. Cats produce it mainly in their skin glands and saliva. When a cat grooms, the protein dries on its fur and flakes off as tiny particles of dander.
Those particles are small and sticky. They float in the air for a long time, cling to fabric and walls, and travel on clothes. That is why cat allergen turns up in homes, classrooms and offices without cats, and why it can linger for months after a cat has moved out.
What people commonly report
Typical reports are itchy, watery eyes, sneezing and a blocked nose within minutes of being around a cat or in a cat home. Some people notice red, itchy skin where a cat has licked or scratched them. People with asthma may find their chest gets tighter.
If your symptoms are worse indoors and all year, cat is worth checking alongside house dust mite and mould.
- Itchy, red eyes after stroking a cat
- Sneezing or a blocked nose in cat homes
- Itchy welts on skin after a scratch or lick
- Cough or wheeze in some people
What about hypoallergenic cats?
No cat breed is free of Fel d 1. Some breeds are marketed as hypoallergenic, but studies have not shown that any breed is reliably low. Amounts vary much more between individual cats than between breeds; male cats that have not been neutered tend to produce more.
If you are deciding whether to adopt a cat, a result is a useful data point, and a conversation with a doctor is a better one.
How the test checks cat
From your finger-prick sample, the lab measures IgE to four single cat proteins (molecular components) as part of 300 allergens and allergen components. Dog, horse, rabbit, guinea pig, hamster and other animals are on the same panel, so you can see whether it is just the cat or animals in general.
A positive result means sensitisation, not a confirmed allergy. Some people are sensitised and live with cats without symptoms. Your lab report gives each value a class from Negative to Very high, to talk through with a doctor.
- Fel d 1: the main cat allergen, specific to cats
- Fel d 2: cat serum albumin, similar to albumins in dog and horse
- Fel d 4: a lipocalin protein from saliva
- Fel d 7: a lipocalin protein, similar to dog's Can f 1
Known cross-reactions
- Other cats, big and small
- Fel d 1-like proteins are found across the cat family, so sensitisation is not tied to one cat or breed.
- Dog and horse
- Some furry-animal proteins (serum albumins, such as Fel d 2, Can f 3 and Equ c 3) are similar across species. A minority of people sensitised to cat also show IgE to dog or horse for this reason.
300 allergens. One test.
A finger-prick sample at home, sent by post. A detailed lab report typically 5 days after the lab receives your sample, and our plain-English guide to reading it. €300, €1 per allergen.
Questions
Am I allergic to my cat?
A blood test can show whether you are sensitised to cat, meaning your blood contains IgE to cat allergen. Whether that is behind your symptoms is a question for a doctor, who combines your result with what you notice and when.
Why do I react in homes without a cat?
Cat allergen particles are tiny and sticky. They travel on clothes and settle in fabrics, so you can meet them in schools, offices and homes where a cat used to live.
Are some cat breeds hypoallergenic?
No breed is free of the main cat allergen, Fel d 1. Levels vary between individual cats more than between breeds. Spending time with a specific cat before adopting is more informative than a breed label.
Can I test without being around a cat first?
Yes. The test measures IgE already in your blood. You do not need to be exposed before taking the sample.