Cat Allergy Trigger Identified as Fel d 1 Protein, Not Fur

Allergy specialists explain that the primary cause of cat allergy is the tiny protein Fel d 1, which is present in a cat’s saliva, skin and urine. When a cat grooms itself, the protein spreads to its fur and dander, making hair merely a carrier for the allergen.

In Spain, more than two million people report pet‑related allergies, with genetics, early exposure and individual immune responses influencing susceptibility. Sonia Saez, veterinarian and communications lead at Purina España, notes that diagnosis typically involves skin‑prick testing by an allergist. Management strategies include regular cleaning, using air purifiers, improving ventilation and, where appropriate, dietary products designed to reduce allergen levels.

While living with a cat is possible for many allergic individuals, Saez advises consulting a health professional to tailor control measures.