Learn what causes the allergies that spoil spring for the millions of allergy sufferers who get runny noses, puffy eyes, and itchy throats this time of year. 

Featuring Calman Prussin, M.D., Associate Program Director of the Allergy and Immunology Clinical Training Program, National Institute of Health 
Video produced by Elaine Seward and XiaoZhi Lim
Series created by Adam Dylewski
Produced by the American Chemical Society