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Asthma triggers
Overview
It is important to know what things make your asthma worse. These are called asthma "triggers." Avoiding them is your first step toward feeling better. The most common asthma triggers are respiratory tract infections caused by viruses such as the flu, common cold, and other viruses. Other triggers are cold and dry air, mold, pets, dust, grasses, pollen, cockroaches, odors from chemicals, and smoke from cigarettes.
Review Date 1/14/2026
Updated by: Linda J. Vorvick, MD, Clinical Professor Emeritus, Department of Family Medicine, UW Medicine, School of Medicine, University of Washington, Seattle, WA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.