[The management of chronic asthma with inhaled beta 2 agonists--regular use? symptomatic use?]

Beta-agonist is a widely used bronchodilator. Although it has an ability to dilate bronchus rapidly, it shows no or minimal relief for severe asthma and no effect on the inflammation which is thought as a most important factor in disease of asthma. Some reports showed that the regular use of inhaled beta 2 agonist induced hypersensitivity of bronchoconstriction, and some showed that the overdose of inhaled beta 2 agonist induced an increase of asthma death. We should discuss how we use inhaled beta 2 agonist systematically now. Depends on the several guidelines, inhaled beta 2 agonist can be used on demand for mild and moderate asthma, and if inhaled beta 2 agonist need to be used regularly for more severe condition of asthma, inhaled corticosteroid and anti-inflammatory agents should be started. Inhaled beta 2 agonist can be used up to 4 times a day. To save the dose of inhaled beta 2 agonist for the control of asthma, the use of a handy peak flow meter will be beneficial.