Asthma Triggers

Overview

When you have asthma, certain things can make your symptoms worse. These things are called triggers.

Things that you're allergic to can trigger your asthma. They may include:

• Dust.
• Dust mites. These are tiny, nearly invisible creatures. They live in bedding, carpet, and furniture.
• Cockroach droppings.
• Pet dander. Dander is loose skin cells (like dandruff) from dogs and cats.
• Indoor mould.
• Pollen.

Your asthma can be triggered by other things too, such as:

• Colds, influenza (flu), and sinus infections.
• Cigarette smoke, air pollution, and fumes from gas, oil, or kerosene heaters.
• Exercise. Many people have symptoms when they exercise.
• Dry, cold air.
• Medicines, such as aspirin or beta-blockers.
• Hormones, including those involved in pregnancy and menstrual periods. A woman's symptoms may change just before or during her period.