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According to Allergy UK, the UK’s leading medical charity dealing with allergies, pets represent the second most important cause of home allergies in humans. In the US, three in ten people have allergic reactions to cats and dogs. And cat allergies seem to be twice as common as dog allergies. Life with cat allergies raises a lot of questions to all of us feline lover, from what they really are and how to recognize them, to treatment and avoidance. Here is what we need to know.

What are cat allergies?

Cat allergies are allergic reactions to allergens produced by cats. Our immune system fights off harmful substances (bacteria and viruses) with antibodies. However, an allergic individual has an oversensitive immune system that attacks harmless proteins present in cat’s saliva and dandruff the same way it would the dangerous substances.

But how do allergic reactions exactly occur? One of the prominent contributors to all allergic reactions is histamine, and its levels have been noted to rise during allergic responses. Mainly stored in mast cells and basophils, histamine is a nitrogenous compound involved in immune responses, inflammatory responses, and regulation of the physiological function in the gut. It also acts as a neurotransmitter in the brain, spinal cord and uterus. Histamine is just one of many mediators in allergic reactions, but it plays a primary role in allergic rhinitis, anaphylaxis and asthma. Allergic rhinitis, or hay fever, is a type of inflammation in the nose that occurs as a result of an immune reaction to allergens in the air. Sign of allergic rhinitis are runny or stuffy nose, sneezing, swelling, watering and itchiness of the eyes.

What causes cat allergies?

Cat allergies are not caused by cat’s fur like it’s widely believed. Cat allergies are caused by the proteins present in cat’s saliva and dandruff, known as allergens. Five cat allergens are currently described in the literature:

1. Fel d 1 (a secretoglobin)

2. Fel d 2 (an albumin)

3. Fel d 3 (a cystatin)

4. Fel d 4 (a lipocalin)

5. IgA (immunoglobin A)

Fel d 1 and Fel d 4 are considered the two major cat allergens. Fel d 1, a secretoglobin produced in cat’s saliva, sebaceous glands and skin, represents the primary cat allergen. On the other hand, Fel d 4 is a major urinary protein expressed in the submandibular salivary gland and deposited in cat’s dandruff.

Accordingly, it is estimated that over 90% of all cat allergies appear as reactions to allergens present in cat’s saliva and skin. Furthermore, in the development of all allergies, genetics seem to play an important role. Therefore, if you have immediate family members experiencing allergies, you are more likely to experience them as well.

What are the symptoms of cat allergies?

The symptoms of cat allergies may appear immediately or up to several days after the contact with cat allergens. Most common symptoms of cat allergies are coughing, sneezing, skin rashes, redness and itchiness of the eyes, runny or stuffy nose, fatigue and irritation of the skin where a cat has scratched, bitten or licked you.

To diagnose any allergy, it’s possible to take allergy tests and pinpoint what exactly the respective individual is sensitive to. There are two types of allergy tests: skin testing and blood testing. Skin testing gives fast results and is usually more affordable than the blood tests. Two types of skin testing can be conducted: a skin prick test and an intradermal skin test. In the first test, an allergist will prick the patient’s skin with a clean needle and deposit a small amount of the allergen on the skin. In the intradermal test, the allergens are injected under the skin. In both tests the patient is typically tested for several allergens at the time. Positive reactions to allergens appear as red, itchy bumps on the skin.

Blood testing includes drawing a blood sample and testing it for antibodies to common allergens. The results take longer and the test tends to be more expensive, but it is considered to be safer and pain free.

Living with a cat allergy

If you or any of your family members suffer from cat allergies, there are some steps that can be taken to reduce the risk of allergic reactions to your beloved feline friend.

Choose a cat that is less likely to provoke an allergic reaction. Some cats are known to produce lower levels of allergens and thus have a higher potential of being hypoallergenic (we will write more about this in the next section of the article).

Keep the distance and hand wash rigorously. It goes without saying that frequent hand washing, especially after handling a cat, is of a very high importance. However, an allergic family member should also be released from certain responsibilities, such as cat grooming or cleaning the litter box.

Restrict your cat to only certain areas. You may consider limiting your feline’s access to rooms where the allergic individual spends a lot of time in (such as bedrooms). If you allow your cat outdoors, keeping it out as much as possible is also an option.

Clean thoroughly and often. As allergens may survive for very long periods of time by themselves, removing and rigorously cleaning anything that can trap and hold the allergens (such as carpets, pillows, blankets etc.) may be helpful at reducing the risk of an allergic reaction. Using HEPA filters in vacuum cleaners is an excellent tool when catching allergens, as they tend to be finer than the regular filters. Central air cleaners can also be useful in order to control the circulation of the cat dander in the air.

Bathe and groom your cat regularly. Regular baths and grooming sessions of you cat are vital for handling the allergic reactions, as this will help reduce the amount of loose dandruff and hair (with the saliva).


Keep that coat healthy. A diet rich in omega-3 fatty acids can help keep the feline coat remain healthy and with minimum dandruff.

Control your allergies with medication. Like all allergies, cat allergies may also be controlled by medications such as antihistamines and decongestants. Antihistamines are available over-the-counter with Zyrtec, Benadryl, Allegra and Claritin being the most popular choices.

Hypoallergenic cats

Some cat breeds have been noted to produce less allergens. These breeds are known as hypoallergenic cat breeds. Due to the lower level of allergens in their saliva, dandruff and urine, they are less likely to cause an allergic reaction in sensitive individuals.

Siberian cats, Devon Rex, Cornish Rex cats, Abyssinian cats and Balinese cats are all noted to produce lower levels of Fel d 1 in comparison to other domestic cats. If you’re sensitive to this allergen, then you are less likely to have an allergic attack when handling these breeds.

Some cat breeds with Balinese cat lineage or ancestry may also have the potential of producing lesser amounts of allergens. These are Oriental Shorthair, Oriental Longhair and some Siamese cats.

It has not yet been established why all these breeds could be hypoallergenic. One theory explains that the Balinese cat’s long-haired gene could be associated with the lower production of the protein allergens. This would explain why the Balinese, also known as the longhaired Siamese, is typically hypoallergenic, but the regular, shorthaired Siamese is not.

Gender and neuter status may also be associated with the levels of allergen production. Female cats produce a lower level of Fel d 1 than males, and neutered males produce a lower level of Fel d 1 than unneutered males. Neutered males produce similar levels of Fel d 1 to those in females.

Regardless of their breed, gender and neuter status, all cats may have a genetic potential of producing higher or lower levels of allergens. If you’re allergic, but have experienced an allergy-free encounter with a feline – chances are that this furry buddy produced lower levels of the allergen(s) you are sensitive to.

If you’re a feline lover like us, but you or your family member suffers from a cat allergy, don’t get immediately discouraged. Sometimes low levels of allergens produced by a cat, combined with the steps to control allergies on your side, may result in a new, happy and pain-free friendship!


Always be careful not to jeopardize your or your feline’s health. Consult with the doctor, pinpoint what exactly triggers your allergies and take your search for the perfect feline from there.