Although the exact cause of asthma is not known clearly yet, but there are some things that often trigger it, such as dust (allergies), cigarette smoke,  cold air, animal dander, exercise, viral infections, or even exposure to chemical substances. If the symptoms of asthma, medicines commonly recommended is inhaler. Besides difficult to breath, asthma sufferers can also feel the other symptoms such as chest pain, coughing, and wheezing. Asthma affects all ages, whether young or old.
The symptoms include:
•    Shortness of breath
•    Chest tightness or pain
•    Chronic coughing
•    Trouble sleeping due to coughing or wheezing (rattling sound in the chest).

Patterns in asthma symptoms are important and can help your doctor make a diagnosis. Pay attention to when symptoms occur:
•    At night or early morning
•    During or after exercise
•    During certain seasons
•    After laughing or crying
•    When exposed to common asthma triggers.

You can controlling asthma as long as you :

- Recognizing and avoiding asthma triggers
- Following asthma management plan created with your doctor.

- Recognize an asthma attack and take action appropriate treatment.
- Using asthma medication recommended by doctors on a regular basis.                       
- Monitor the condition of your airways.

source : http://www.aaaai.org/conditions-and-treatments/asthma

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