Animal dander is composed of tiny flakes of skin that are shed by warm-blooded animals, such as cats, dogs, rodents, birds, and other animals with fur or feathers. Dander is similar to dandruff in humans, but it is much harder to see. Pet dander is the most common source of a pet allergy, but people can also be allergic to the proteins that are present in pet saliva, urine, and feces. Animal dander can trigger an allergy and cause upper and lower respiratory problems such as congestion, sneezing, runny nose, chest tightness, and wheezing. Other symptoms include watery eyes, itching, and eczema or rashes. Pet dander and other pet allergens may linger in the air for a longer time than other allergens because they are microscopic and jagged in shape, making it easy for them to become airborne and stick to furniture, bedding, fabrics, and even be carried on items into and out of the home. To limit pet dander and avoid allergies, it is recommended to bathe pets weekly, use products that are labeled specifically for pets, and ask veterinarians or other animal care professionals for their shampoo recommendations.