How Pet Allergies Work
Pet allergies are not caused by fur itself — they are caused by proteins produced in the animal's skin, saliva, urine, and sebaceous glands. These proteins become airborne on tiny skin flakes (dander) or dried saliva particles and trigger IgE-mediated allergic reactions in sensitised individuals.
Symptoms can include sneezing, runny nose, itchy eyes, skin reactions, and worsening asthma. The severity depends on the degree of sensitisation, the allergen load in the environment, and which specific components you are sensitised to.
What ALEX3 Detects: Key Pet Allergen Components
Standard whole-extract RAST tests tell you whether you have IgE to "cat" or "dog" — but not which specific proteins are responsible. ALEX3 goes deeper, testing at the molecular component level:
🐱 Cat allergens
- Fel d 1 — major allergen (saliva, skin)
- Fel d 2 — albumin (cross-reactive)
- Fel d 4 — lipocalin
🐶 Dog allergens
- Can f 1 — major allergen (skin)
- Can f 2 — skin protein
- Can f 5 — prostate protein (males)
- Can f 6 — lipocalin
🐴 Horse allergens
- Equ c 1 — lipocalin
- Equ c 3 — albumin (cross-reactive)
Why Component Testing Matters
Understanding which allergen components you react to has real clinical implications:
- Fel d 1 vs Fel d 2: Sensitisation to Fel d 1 is primary cat allergy. Sensitisation to Fel d 2 (albumin) may indicate cross-reactivity with pork and bird meat — explaining reactions you didn't expect.
- Can f 5: This protein is produced primarily in the prostate of intact male dogs. If your main sensitisation is to Can f 5, you may react much more strongly to an intact male dog than to a female or neutered male — which explains why some dogs affect you and others don't.
- Allergen immunotherapy planning: Component profile is used by allergy specialists to select the right immunotherapy preparation and predict treatment response.
Cross-reactivity between pets and pollen: Some pet allergen components (albumins like Fel d 2, Can f 3, Equ c 3) cross-react with allergens in pollen and certain foods. ALEX3 identifies these cross-reactive components, which can explain otherwise puzzling reactions.
Practical Advice for Pet Allergy Sufferers
Allergen avoidance is the first-line recommendation, but this is not always practical or desired — particularly if you are allergic to your own pet. Several measures can help reduce allergen load in the home:
- Keep pets out of the bedroom
- Use HEPA air purifiers in living spaces
- Wash hands after contact
- Use allergen-reducing sprays on upholstery
- Regular vacuuming with a HEPA-filter vacuum
For those seeking longer-term relief, allergen immunotherapy (desensitisation) through a specialist allergy clinic can significantly reduce sensitivity over time. A confirmed ALEX3 component profile is valuable before starting this process.
Book ALEX3 Allergy Testing
If you suspect a pet allergy — or want to understand which specific allergens are driving your symptoms — book an ALEX3 allergy test at Lambert Medical Practice. Your GP will review the results and discuss management options with you.