Cat Allergies: Causes, Symptoms, Treatments and Testing

As of 2024, around 29% of American households own a pet cat; this equates to around 47 million homes. While many households love their feline friends, cats can produce problems for some. Cats are one of the most frequently encountered household pets, contributing to many happy household moments. However, because of their popularity, they are also a major source of allergens. Approximately 10% of the US population has pet allergies, which may present in many forms and range widely in symptoms and reactions.

An animal’s saliva, urine, and skin cells are all potential allergy triggers. Each contains specific proteins that can activate the immune system and cause adverse symptoms, be it a minor skin rash or a full-blown asthma attack. Pets, and more notably cats, are suggested to be the third leading cause of allergic asthma, after mites and pollens. However, cat allergies are often misunderstood. So, if you or somebody you know is allergic to cats, or you think you may have an allergy to our feline friends, then read on to discover more about cat allergy symptoms, causes, treatments, and testing. 

What causes cat allergies?

Our immune system protects us from outside invaders, such as bacteria, viruses, fungi, and toxins. Allergies are the immune system’s response to a substance or (more specifically) an allergen. 

Why Are People Allergic To Cats?

The main sources of cat allergens are salivary, sebaceous (skin cells also known as dander), and urinary.

Proteins found within these sources trigger our immune response, often via airborne particles that can reach our lungs (specifically the small bronchioles).

The most prominent cat allergen is a protein called Fel d 1. It has been shown that cat owners can inhale almost as much Fel d 1 in a single day as they do pollen allergens in a whole year! So, if you were doubting the potential seriousness of a cat allergy, maybe this can help you understand that it’s not something to trifle with. 

The official allergen site, approved by WHO, records a total of 8 different cat allergens. 

How common are cat allergies?

The increase in pets within the home — a recent survey found 70% of American households own a pet — has led to an increase in the prevalence of cat allergies. For example, in Europe, approximately 26% of adults have consulted their doctor for a suspected cat allergy. Meanwhile, in the US, it was estimated that 12.1% of the population over the age of 6 were sensitive to cats.

It is estimated that around 10-20% of human adults globally are allergic to our feline friends. It is also estimated that, in the US, up to 30% of people are allergic to cats or dogs, and you are more than twice as likely to be allergic to a cat than a dog. So, while cat allergies are not overly common, they are significantly more common than you may at first think. 

What are the symptoms of a cat allergy?

The symptoms of a cat allergy can range from mild to severe. Some of the symptoms often include:

• Sinus irritation and sneezing
• Runny nose
• Itchy, watery eyes
• Congestion
• Skin rash and eczema
• Itching and dryness
• Redness and swelling
• Difficulty breathing
• Chest tightness

If you suspect you could be having a serious allergic reaction (anaphylaxis), please seek immediate treatment in a hospital.

What can a cat allergy look like?

Depending on the levels of allergen and a person’s sensitivity, reaction to cat allergens may be immediate or not occur until several days after contact. This means if you have a mild cat allergy or lower sensitivity and you had a nice run-in with your friend’s cat (filled with lots of cuddles) and you find yourself exhibiting allergen-like symptoms, even days after the event, it could be the feline that’s causing it. 

It is common to get itchy eyes after petting a cat and then touching your eyes. A cat scratch or lick on your skin can cause the area to become red and itchy, possibly causing hives (a rash with raised red patches). Cat allergies can also trigger an asthma attack if you have asthma. So, while these are some of the potential ways a cat allergy could present itself, what a cat allergy actually looks like will depend on a number of factors. 

How long do cat allergy symptoms last after exposure?

Cat allergens are particularly persistent and can remain in the home for at least 6 months after the cat is no longer there. Therefore, a person who is allergic to cats may continue to have symptoms even after a cat is no longer present. However, symptoms should desist with the correct treatment plan.

As a general rule, mild symptoms or reactions should fade within a few hours of not being exposed to the allergen, while more severe reactions can last a couple of days. 

What does a cat allergy look like in children?

An infant who is sick, has difficulty sleeping, has trouble breathing, develops rashes, or has unexplained respiratory symptoms after being exposed to cat allergens may be allergic. If you have any concerns about your child’s health, you should always consult your physician.

How to manage cat allergies

Taking preventative measures can help you to avoid cat allergy symptoms, whilst medications can help to alleviate symptoms when they arise.

What medications can treat cat allergies?

In order to treat and alleviate your cat allergy symptoms, your doctor may suggest:

• Antihistamines reduce the production of an immune system chemical that is active in an allergic reaction, and they help relieve itching, sneezing, and a runny nose.
• Corticosteroids delivered as a nasal spray can reduce inflammation and control symptoms of cat allergies.
• Decongestants can help shrink swollen tissues in your nasal passages and make it easier to breathe through your nose
• Leukotriene modifiers block the action of certain immune system chemicals.
• Immunotherapy. You can “train” your immune system not to be sensitive to an allergen. Immunotherapy is delivered through a series of allergy shots.
• Nasal irrigation. You can use a specially designed squeeze bottle to flush thickened mucus and irritants from your sinuses with a prepared saltwater (saline) rinse.

How to prevent cat allergies

Other ways to minimize cat allergy symptoms when living with cats include:

• Avoid hugging and kissing pets if you are allergic to them.
• Wash your hands regularly, especially after coming in contact with furry animals.
• Keeping pets out of specific areas such as your bedroom can reduce allergy symptoms since you spend about eight hours every day in this room. Keeping your pet off upholstered furniture can help too.
• Grooming: have someone who doesn’t have allergies brush the cat regularly (outside, not indoors).
• Vacuuming: regularly vacuum using a double or micro-filter bag in the vacuum to reduce the amount of pet allergen present in carpeting that leaks back into the room air.
• Air purifiers: use HEPA air cleaners, as these can be a big help in removing unwanted allergenic particles from the air.
• Remove carpeting and rugs that can trap pet dander and other allergens. Low-pile carpets can reduce trapped dander.

Keeping animals outside may only be a temporary solution since pet dander will eventually make its way indoors (as it is carried on clothing).

How long does a cat allergy last – is it a lifetime?

Cat allergies can come and go. Some people who are initially allergic to cats may become tolerant over time, while others may develop a more severe allergy. So, even if you have a sudden cat allergy, you can at least know that it may not necessarily be for life. 

Can you get rid of a cat allergy?

There is no cure for cat allergies. However, there are effective ways to build up immunity against the allergen, such as immunotherapy.

Can you become less allergic to cats over time?

People with cat allergies manage rather than cure their condition – usually with medications such as antihistamines, and by trying to avoid anything that causes a reaction. In many cases, you don’t have to make drastic lifestyle changes.

Many children may outgrow allergies (e.g. reactions to milk or eggs).

Allergen-specific immunotherapy (SIT) is a treatment option for patients with allergic rhinitis triggered by aeroallergens (such as pollen, animal dander, or dust) when pharmacological therapies, such as antihistamines, are insufficient.

How long does cat dander last on clothes?

Cat dander can last on clothes for several months even after a cat comes into contact with them. However, properly washing your clothes at a higher temperature is more effective at removing dander. The exact duration depends on environmental factors like humidity and airflow, but dander particles are known for their ability to cling to fabrics.

How to diagnose cat allergies

Like all forms of allergy testing, the aim is to detect allergen-specific IgE (Immunoglobulin E) to determine if you have a pet dander allergy. Whether done with a Home-to-Laboratory Allergy Test Kit or through your physician, IgE detection via blood testing will effectively validate an allergy and, if an allergy exists, enable you to seek the best form of treatment or lifestyle changes.

Which types of tests are available?

If you suspect that you are suffering from a cat allergy, you may want to take a test. Proper allergy testing is crucial in situations in which pet dander is the suspected trigger.

To determine if you have an allergy to cat dander, either a skin prick test or a blood test is recommended for the most accurate results. Skin prick tests are usually done by a physician in a clinical setting, whereby a very small amount of the allergen is pricked onto the skin. In the case of reaction, an allergy can be validated.

How to test for cat allergy at home?

Lab-Certified blood tests are arguably more accurate, and in some cases, they’re easier to administer. While sometimes administered in a clinical setting, at-home allergy tests make it convenient for individuals to determine their allergies from the comfort of their homes.