Allergy-related symptoms can occur after you are around certain animals. These substances are usually found indoors and do not cause symptoms for most people. Allergies occur when the immune system over-reacts to substances (allergens) that are usually harmless.
When a person with allergies breathes in an allergen, the body releases histamine and other chemicals as part of the immune response. This causes itching and swelling, mucus production, and in serious cases, hives and rashes, as well as other symptoms. Symptoms vary in severity from person to person.
Most environmental allergens contact the skin or eyes, or are inhaled. Therefore, most symptoms affect the skin, eyes, or the breathing passages. People who are allergic to certain animals are rarely allergic to the animals’ fur or feathers. They are actually allergic to proteins produced on the skin (dander) that the animal sheds. These proteins are also found in the animal’s saliva and urine, particularly cats. You can come into contact with animal saliva if the pet licks you, if you touched the pet after it has groomed itself, or if you touch an object that the animal has recently licked or chewed. Animals often roll around in the grass and leaves, and can carry pollens and molds in their fur or hair.