What allergen causes allergies to cats? - briefly
The primary allergen responsible for cat allergies is a protein called Fel d 1, which is found in cat saliva, skin, and urine.
What allergen causes allergies to cats? - in detail
The primary allergen responsible for cat allergies is a protein called Fel d 1, which is produced in the sebaceous glands of a cat’s skin, salivary glands, and, to a lesser extent, in the anal glands. This protein is highly potent and is the most common trigger of allergic reactions in humans. Fel d 1 is secreted onto the cat’s fur through grooming, as it is present in saliva, and is also shed with skin cells, known as dander. These microscopic particles become airborne and can be inhaled, leading to allergic symptoms such as sneezing, runny nose, itchy eyes, and asthma in sensitive individuals. Even in environments where cats are not present, Fel d 1 can persist for months due to its ability to adhere to surfaces like furniture, clothing, and carpets. Interestingly, Fel d 1 is not exclusive to any specific breed of cat, although some breeds may produce lower levels of the protein. The immune system of allergic individuals mistakenly identifies Fel d 1 as a harmful substance, triggering an immune response that results in the release of histamine and other inflammatory chemicals. This reaction is what causes the discomfort associated with cat allergies. Reducing exposure to Fel d 1 can help alleviate symptoms, but complete avoidance is challenging due to its widespread distribution and persistence.