Causea of asthma

It isn't clear why some people get asthma and others don't, but it's probably due to a combination of environmental and genetic (inherited) factors.

Asthma triggers are different from person to person. Exposure to various allergens and irritants can trigger signs and symptoms of asthma, including:

    * Airborne allergens, such as pollen, animal dander, mold, cockroaches and dust mites
    * Respiratory infections, such as the common cold
    * Physical activity (exercise-induced asthma)
    * Cold air
    * Air pollutants and irritants such as smoke
    * Certain medications, including beta blockers, aspirin and other nonsteroidal anti-inflammatory drugs
    * Strong emotions and stress
    * Sulfites, preservatives added to some perishable foods
    * Gastroesophageal reflux disease (GERD), a condition in which stomach acids back up into your throat
    * Menstrual cycle in some women
    * Allergic reactions to foods such as peanuts or shellfish

Risk factors

Asthma is common, affecting millions of adults and children. A growing number of people are diagnosed with the condition each year, but it isn't clear why. A number of factors are thought to increase the chances of developing asthma. These include:

    * A family history of asthma
    * Frequent respiratory infections as a child
    * Exposure to secondhand smoke
    * Living in an urban area, especially if there's a lot of air pollution
    * Exposure to occupational triggers, such as chemicals used in farming, hairdressing and manufacturing
    * Low birth weight
    * Being overweight

When to seek medical advice

Three key circumstances may lead you to talk to your doctor about asthma:

    * If you think you have asthma. If you have frequent coughs that last more than a few days or any other signs or symptoms of asthma, see your doctor. Treating asthma early, especially in children, may prevent long-term lung damage and prevent worsening of the condition over time.
    * To monitor your asthma after diagnosis. If you know you have asthma, work with your doctor to keep it under control. Good asthma control not only helps you feel better on a daily basis, but also can prevent a life-threatening asthma attack.
    * If your asthma symptoms get worse. Contact your doctor right away if your medication doesn't work for you. Asthma changes over time, and you'll need periodic adjustments to your treatment to manage your symptoms. Don't try to solve the problem by taking more medication without consulting your doctor. Overusing asthma medication can cause side effects and may even make your asthma worse.

Severe asthma attacks
Severe asthma attacks can be life-threatening and require emergency treatment. If your asthma isn't getting better with quick-relief medications, seek emergency help right away. Work with your doctor ahead of time to determine what to do when your signs and symptoms worsen — and when you need emergency treatment. Signs of an asthma attack that needs emergency treatment include:

    * Rapid worsening of shortness of breath or wheezing
    * No improvement even after using short-acting bronchodilators
    * Shortness of breath with minimal activity