Acute Relief of Exercise-Induced Bronchoconstriction by Inhaled Formoterol in Children With Persistent Asthma
Relief therapy is pivotal to any asthma management plan. The aims of such a therapy are rapid lung function improvement and preferably prolonged action with the option of repeated dosing without risk of side effects. In addition, bronchopro-tection against asthma triggers such as exercise is desired. add comment
Inhaled formoterol is a full (32-agonist. Onset of bronchodilation has been reported to be similar to that of terbutaline and salbutamol in both stable and acute severe asthma and with similar systemic activity. Increasing the dose of formoterol provides an increased therapeutic effect during asthma worsening, as the standard therapeutic dose is at the steep part of its dose-response curve.’ This allows repetitive dosing during days of exacerbations without concerns of safety and potentially increases the effect to the maximal level. In addition, single doses provide a sustained, significant bronchodilation and bronchoprotection over 8 to 12 h in contrast to the 2 to 4 h after short-acting (32-agonist (SABA) as assessed by methacholine challenge, exercise chal-lenge, and cold dry-air hyperventilation.
This profile seems useful for relief therapy and superior to that of SABA, and therefore we previously suggested a reappraisal of the position of formoterol in pediatric asthma management. Indeed, in adult asthmatics the use of formoterol as relief therapy has since been reported to reduce exacerbation risk compared to the use of SABAs.
Exercise is one of the important triggers of asthma symptoms in children necessitating relief therapy, and adherence to prophylactic pre-exercise (32-agonist treatment in school children might be poor and rarely applicable for spontaneous activity in childhood. Therefore, to research a reappraised positioning of formoterol as rescue therapy in pediatric asthma, we have compared the potential of formot-erol and terbutaline for acute relief of exercise-induced bronchoconstriction (EIB) in children.