Purina reveals a revolutionary approach to managing a major cat allergen: the science behind reducing active Fel d1 at its source in cats’ saliva


The article is sponsored content brought to you by the Purina Institute – Advancing Science for Pet Health.

As many as 1 in 5 adults, worldwide, suffer from sensitivities to cat allergens.1,2 The main recommendation for people with these sensitivities is to avoid cats.3 After more than 10 years of research, Purina scientists discovered a new approach that can give people and cats a chance to stay closer together. This safe and proven approach uses cat food coated with an egg product ingredient that neutralizes the major cat allergen, Fel d 1, at its source in cats’ saliva before the allergen gets into the environment.4,5 This offers people sensitized to cat allergens a way to reduce their exposure to the allergen, not the cat.

A common problem for people and cats

Cat allergens can impair quality of life for allergy sufferers by interfering with daily activities.6,7 They also limit interactions between the allergic person and cats. Allergy to cats is a common reason for relinquishment to shelters,8-13 as well as a barrier to cat ownership.9,14

Fel d 1 is the major cat allergen

Fel d 1 is produced primarily in cats’ salivary and sebaceous glands, spread throughout the hair coat during grooming, and shed into the environment with hair and dander.15,17 All cats produce Fel d 1 regardless of breed, sex, age, hair length, hair colour, or body weight.3,7,15,17-21 The function of Fel d 1 is not yet known, but studies suggest a pheromone or chemical signalling role.2,15,22

A new approach to allergen management

Most methods of allergen management are effort-intensive, costly, and focus on managing exposure to the allergen in the environment.7,23 With Purina’s approach, the cat simply eats a nutritious food coated with an egg product ingredient containing anti-Fel d 1 antibodies.4,5 As the cat chews the kibble, the antibodies bind to active Fel d 1 in the cat’s saliva. Once bound, Fel d 1 is neutralised, and no longer recognized as an allergen. The neutralised Fel d 1 is transferred to the cat’s hair and dander during grooming, ultimately reducing active Fel d 1 levels in the environment. This approach does not stop a cat’s natural production of Fel d 1. A comprehensive safety study confirmed the ingredient is safe for cats.24

Neutralized Fel d 1

Proven science

In peer-reviewed, published studies4,5 cats showed significant reductions of active Fel d 1 in their saliva, and on their hair and dander, when fed a diet coated with an egg product ingredient containing anti-Fel d 1 antibodies. 

  • 97% of cats showed reduced active Fel d 1 on their hair and dander.5 
  • 47% reduction, on average, of active Fel d 1 on cats’ hair beginning with the third week of feeding the diet.5 
  • 86% of cats had a reduction of at least 30% from baseline levels.5 

Reducing active allergen levels can have real and positive impacts.25,26 Cat-allergic people exposed to dander from cats fed this diet showed significant reductions in nasal allergy symptoms and some ocular symptoms.25 This revolutionary new approach reduces exposure to the allergen, not to the cat—bringing cats and people closer together.

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