Cat allergy
Allergy to cat dander, saliva and urine proteins.
About cat allergy
Cat allergy is among the most common animal allergies and is an IgE-mediated reaction to proteins the cat produces, chiefly the well-established major allergen Fel d 1. This protein is found in saliva, skin glands and urine, and is spread across the coat during grooming; it is the dander (tiny skin flakes) and dried saliva, not the fur itself, that carry it. Fel d 1 is small and remarkably sticky, so it clings to clothing and upholstery and builds up in homes and public spaces. No breed is genuinely safe: hypoallergenic cats are a myth, as every cat makes this protein.
Symptoms usually begin within minutes to hours of contact and include sneezing, a runny or congested nose and itchy, streaming eyes. In people prone to asthma or eczema, exposure can set off wheezing or a skin flare. Because the allergen travels so readily, some react in schools, offices or on public transport where cats have never been. Reactions are typically bothersome rather than life-threatening.
A GP or allergy clinic can confirm the cause with a skin-prick or specific-IgE blood test. Removing the cat is most effective but frequently unwanted, so reduction steps matter: keeping the cat out of bedrooms, HEPA filtration and vacuuming, frequent cleaning and washing hands after contact. Antihistamines, nasal sprays and eye drops relieve symptoms, and immunotherapy may be offered in selected cases. See your GP if symptoms are persistent or if asthma is involved.
Common triggers
- Cat and products containing it
Symptoms
- Sneezing and a runny or blocked nose
- Itchy, watery eyes
- Skin redness where the animal licked or touched
- Coughing or wheezing
- Worsening of asthma
Avoidance & management
- Limit contact with the animal
- Keep pets out of bedrooms
- Wash hands and clothes after contact
- Use air filtration and vacuum often
- Take prescribed antihistamines
Sources & references
Allergy safety: what everyone should know
Mild-to-moderate reaction signs
- Itching, hives or a raised rash
- Swelling of lips, face or eyes
- Tingling mouth, sneezing, runny nose
- Stomach pain, nausea or vomiting
Anaphylaxis — call 999 (UK) or 112 (EU) immediately
- Difficult or noisy breathing, wheeze, persistent cough
- Swelling of the tongue or tightness in the throat
- Dizziness, collapse, pale and floppy (young children)
- Use an adrenaline auto-injector (e.g. EpiPen) at once if prescribed, then call an ambulance even if symptoms improve
Allergy or intolerance? A true allergy involves the immune system and can escalate quickly; an intolerance (e.g. lactose intolerance) is unpleasant but not life-threatening. The symptoms overlap, so self-diagnosis is unreliable.
Getting tested: home-testing kits based on IgG are not diagnostically valid. If you suspect an allergy, ask a GP for referral to an allergy clinic for skin-prick or specific-IgE testing and a supervised food challenge where appropriate.