Cat Allergy? I’d rather have Malaria

Cat allergy usually becomes a problem the moment a cat enters your life — a partner moves in with one, the kids start asking, or you’re trying to work out why you wheeze every time you visit certain homes. The question is rarely abstract. It’s practical: is this really cat allergy, how serious is it, and what can you do without turning daily life into a constant clean-up?

Cat allergens behave like fine dust that lingers and travels. A clear diagnosis matters, because the right mix of avoidance, medicines, and (for some people) allergen immunotherapy can make symptoms manageable — while ignoring it can worsen asthma control or lead to repeated flare-ups.^{1, 2}

What a “cat allergy” actually is

A cat allergy is an immune reaction to specific proteins made by cats — not to the fur itself. The best-known is Fel d 1, a major cat allergen produced largely in saliva and skin secretions. As cats groom, the allergen coats the fur and skin flakes, then becomes airborne on tiny particles and settles through the home like grit.^{3, 4}

Cat allergens can also be found in places with no cat at all, carried on clothing and soft furnishings. In studies of homes of people with asthma, cat allergen has been detectable even when most households did not own a cat.⁵

Common symptoms (and when they’re more than “a bit of hay fever”)

Cat allergy often looks like allergic rhinitis (hay fever) and conjunctivitis:

• sneezing, blocked or runny nose
• itchy, watery eyes
• cough, chest tightness, wheeze (especially if you have asthma)
• skin symptoms such as itch or hives after contact

Symptoms can range from mild irritation to asthma flare-ups that need urgent treatment. If cats reliably trigger wheeze, breathlessness, or nighttime coughing, treat it as a respiratory issue, not just a nuisance.^{2, 6}

Why reactions can keep happening after the cat is gone

Fel d 1 is persistent and “sticky”. It clings to carpets, couches, bedding, and clothing, and it can take months for levels to fall after a cat is removed — especially in carpeted homes and rooms with soft furnishings.³

Diagnosis: how to confirm it (without guessing)

Because cat allergy can mimic colds, dust mite allergy, mould sensitivity, or seasonal pollen allergy, a proper assessment is worth the time. Clinicians usually combine your history (what happens, where, how quickly) with allergy testing such as:

• Skin prick testing (often the quickest way to check sensitisation)
• Blood testing for specific IgE, sometimes including component testing (for example, to Fel d 1) in selected cases^{4, 7}

If you have asthma, mention cat exposure specifically. Cat sensitisation is strongly associated with asthma symptoms in many people, and it can change how your asthma is managed day to day.⁸

Managing symptoms day to day

The most reliable way to reduce symptoms is to reduce exposure to the allergen. When that’s not fully possible, aim for layered control: fewer allergens in the air and on surfaces, plus medicines that steady the immune response.

Practical exposure reduction at home

• Keep cats out of the bedroom and shut the door. The goal is one room where your air and bedding stay as low-allergen as possible.⁶
• Focus on soft furnishings: wash bedding regularly, and consider reducing rugs, fabric throws, and heavy curtains where allergens accumulate.⁶
• Vacuum with a HEPA-filter vacuum and dust with a damp cloth to avoid re-suspending particles.⁶
• Consider a HEPA air cleaner in the bedroom or main living area. It won’t “solve” cat allergy, but it can reduce airborne particles as part of a broader plan.⁶

Medicines that commonly help

For many people, symptom control is best when it’s steady and preventive, not just reactive after exposure.

• Antihistamines can reduce sneezing, itch, and runny nose.
• Intranasal corticosteroid sprays are often the most effective single treatment for persistent allergic rhinitis symptoms, especially nasal blockage.⁹
• Asthma medicines may need review if cats trigger wheeze or chest tightness; uncontrolled asthma and allergen exposure are a risky pairing.^{2, 6}

Decongestant sprays can briefly open the nose, but using them for more than a few days in a row can worsen congestion (rebound). If you’re reaching for them often, it’s a sign your baseline treatment needs adjusting.⁶

Allergen immunotherapy (desensitisation): when it’s considered

Allergen immunotherapy aims to change how your immune system responds over time by giving carefully controlled doses of the allergen, usually over several years. It’s generally considered when avoidance and standard medicines aren’t enough, or when symptoms significantly affect daily life.^{1, 10}

Immunotherapy needs specialist oversight because allergic reactions can occur, and it isn’t suitable for everyone. If your symptoms are severe, or if cat exposure is unavoidable (shared custody, family members, workplace), ask your GP about referral to an allergy specialist to discuss whether it’s appropriate in your case.^{1, 10}

“Hypoallergenic cats” and other common traps

No cat breed is truly non-allergenic. All cats produce allergens such as Fel d 1, and individual cats can vary widely — which is why someone may react strongly to one cat and less to another, without it being a reliable rule you can buy your way into.³

When to get urgent help

Seek urgent medical care if cat exposure triggers significant breathing difficulty, rapidly worsening wheeze, or symptoms that don’t settle with your usual asthma reliever plan. If you have asthma and notice it is consistently worse around cats, organise a review — repeated flare-ups can quietly erode control over time.^{2, 6}

Final thoughts

Cat allergy is common, persistent, and often underestimated because it can look like “just a runny nose”. But the biology is straightforward: airborne proteins such as Fel d 1 spread, stick, and linger. A confirmed diagnosis, practical exposure reduction, and the right medicines can bring the situation back into balance — and for a smaller group, allergen immunotherapy may be worth discussing.^{1, 2}

References

1. healthdirect (Australian Government): Allergen immunotherapy
2. Mayo Clinic: Pet allergy (diagnosis and treatment)
3. Thermo Fisher Scientific (Allergen Encyclopedia): Cat dander (e1) and Fel d 1 persistence
4. PubMed: The major cat allergen, Fel d 1, in diagnosis and therapy
5. PubMed: Major cat allergen (Fel d I) levels in homes of patients with asthma
6. The Royal Children’s Hospital Melbourne: Allergy and Immunology (includes inhalant allergen immunotherapy and specialist care context)
7. Thermo Fisher Scientific (Allergen Encyclopedia): Fel d 1 (e94) component information
8. PubMed: Fel d 1 as a major cat allergen and its role in allergic sensitisation (mechanistic study)
9. American Academy of Family Physicians: Treatment of allergic rhinitis
10. The Royal Children’s Hospital Melbourne: Allergen desensitisation (pre-referral guidance and safety notes)