Cat Allergy: What Works, What Doesn’t, and What’s Next

At the 2025 French-Speaking Allergology Congress in Paris, Dr. Sylvie Leroy presented an overview of strategies to reduce cat allergies, focusing on the Fel d 1 protein, the main allergen produced by cats. With over 16 million cats in French households, symptoms such as rhinitis, eczema, and asthma are common, but current interventions offer only partial or temporary relief.

Conventional advice—restricting cats from bedrooms, removing carpets, and using HEPA filtration—can reduce airborne allergens, though symptom improvement is inconsistent. Bathing cats lowers Fel d 1 only briefly. Diets enriched with egg-derived IgY antibodies show promise in lowering allergens, but studies lack controls and rely on self-reporting.

Emerging approaches include vaccines (e.g., HypoCat) that trigger cats to produce neutralizing antibodies, reducing Fel d 1 by up to 50%, though long-term effects remain unclear. Gene-editing research using CRISPR-Cas9 has nearly eliminated Fel d 1 in experimental cats, raising ethical questions. No cat breed is fully hypoallergenic.