Animal Dander
Dander from animals may worsen your asthma. Pets produce dander that can put asthmatics at risk. These pets include dogs, cats, birds, rabbits, and rodents. Pet dander is the protein in skin flakes, urine, feces, saliva, and hair, and it can trigger asthma symptoms. These proteins are tiny, and they travel through the air and can land on a body part. They can then easily be transferred to the nose or the mouth and thus inhaled. Symptoms may occur immediately, or they may not develop until 8 to 12 hours later.

