Animal Dander All warm-blooded animals shed tiny flakes from their skin called dander (it's like dandruff in humans, but much harder to see). When someone is allergic to animals, dander could be causing the problem. Pet dander can be trouble for people who have asthma because if they're allergic to dander, it can make breathing problems worse. Back to Articles Related Articles Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor. © 1995-2021 KidsHealth®. All rights reserved. Images provided by The Nemours Foundation, iStock, Getty Images, Veer, Shutterstock, and Clipart.com.