Most people can think of several things that make their asthma worse. These are known as ‘triggers’, and a variety of triggers can contribute to your asthma, including. allergens, viral infections, pollutants and drugs.
A trigger is anything that irritates the airways and causes the symptoms of asthma to appear. Everyone's asthma is different and you will probably have several triggers. It can be difficult to identify exactly what triggers your asthma, as the effects can take up to 4-6 hours before you notice them – or even longer.
Reducing your exposure to some of these risk factors improves your control of asthma and reduces the need for drugs. For example, you can avoid tobacco smoke or foods and additives known to cause symptoms of asthma.
In the case of other know triggers (e.g. allergens, viral infections and pollutants) measures should be taken to avoid these as far as possible. Many patients react to multiple factors that are common in the environment. Avoiding these factors is usually impractical and very limiting for people with asthma and allergies.
Medications to maintain asthma control have an important role because patients are often less sensitive to risk factors when their asthma is under proper control.
Often it's not just one trigger that sets off an episode of asthma but a mixture of several triggers at about the same time.