What is it and who gets it? Asthma is a condition whereby the smaller airways of the lungs constrict (or narrow) from time to time, causing typical symptoms. The duration and extent of narrowing vary and they determine the degree of severity of the disease. Asthma affects people of all ages, however, it tends to starts in childhood and runs in family. Having said that, certain asthma sufferers have no family members who have asthma.

What are the symptoms of asthma? Typical symptoms are a cough, wheezing, chest tightness and shortness of breath. The severity of asthma can usually be classified according to the degree of symptoms. Each episode of symptoms may last from a hour to several days if left untreated. Death is a known but uncommon cause of severe untreated asthma.

Symptoms of mild asthma: Episodes of symptoms only during exercise or triggered by a chest or an upper respiratory infection. You are usually symptom- free between episodes.

Symptoms of moderate asthma: You display symptoms from time to time. Symptoms tend to be worst at night and early in the morning. You may be awakened at night with a tight chest and coughing.

Symptoms of severe asthma: You have symptoms on most days. You may find it hard to talk. Frequent hospitalization for asthma is also one of the criteria for severe asthma.

What causes asthma? Asthma occurs as a result of inflammation in the lower, smaller airways. No one is entirely sure why the inflammation occurs. As a consequence of the inflammation, the sensitive airway constricts, making it hard for air to get in and out of the lungs. This leads to symptoms like wheezing, breathless, chest tightness and a cough. Not only that, the inflammation also stimulates the airway to pump out extra mucus, which causes the airway to obstruct further.

What are the exacerbating factors of asthma or what can make it worse? Asthma symptoms may be triggered by certain factors. Occasionally, we do not know why it becomes worse. It is possible to avoid certain triggers to help to reduce symptoms. Identifiable triggers include:

Exercise. Exercise is a known trigger for asthma. Having said that, you should not refrain yourself from doing sports and exercises. They are actually good for your asthma. It is possible to prevent asthma symptoms while exercising by using an inhaler before you exercise.

Pollen and moulds. This is particular evident during season of hay fever.

Infection. Viral respiratory tract infections like flu or common cold are common triggers.

Smoking and air pollution.

Some medicine. Certain medicines are known to constrict smaller airways in the lungs, they include aspirin, beta-blockers and some eye drops for glaucoma.

House dust mites.

Some food. We do not know why certain food can bring up symptoms of asthma. Food like nuts, eggs and fish can sometimes trigger off an asthma attack in people who have known asthma. However, this is not a common trigger.

Emotion. Asthma has nothing to do with your 'nerve'. However, certain emotions like stress, laughing, anxiety can all cause symptoms of asthma.