**3. Conventional treatment of childhood asthma**

The optimal treatment of childhood asthma depends upon a number of factors, including the child's age, the severity and frequency of asthma attacks, and the ability to properly use the prescribed medications [2]. For the vast majority of children, asthma treatment can control symptoms, allowing the child to participate fully in all activities, including sports. Identifying and avoiding asthma triggers, the factors that set off or worsen asthma symptoms, are essential for preventing asthma flare-ups [2]. Common asthma triggers generally include allergens (such as dust, pollen, and furred animals), respiratory infections, irritants (such as tobacco smoke, chemicals, and strong odors or fumes), physical activity, certain medicines (such as beta blockers, aspirin, or other nonsteroidal anti-inflammatory medications), and emotional stress [2]. After identifying potential triggers of asthma, the parent and health care provider should develop a plan to deal with the triggers. If possible, the child should completely avoid or limit exposure to the trigger [2].

The long-term goals of asthma management are to achieve good symptom control and to minimize future risk of exacerbation, fixed airflow limitation, and side effects of treatment [2]. In control-based asthma management, pharmacological and nonpharmacological treatment is adjusted continuously in a cycle that involves assessment, treatment, and review of the response [2]. Asthma severity is determined by considering the following factors: the symp‐ toms reported over the previous 2 to 4 weeks, the current level of lung function (FEV1 and FEV1/FVC values), and the number of instances of exacerbation requiring oral glucocorticoids per year [2]. The classification of severity in children aged 5–11 years or in adolescents over the age of 12 years is similar to that in adults [2]. The severity in children under the age of 4 years, however, is classified somewhat differently and includes intermittent, mild persistent, moderate persistent, and severe persistent asthma [2].

#### **3.1. Categories of asthma medications**

Medication for asthma is mainly divided into two categories: controller medications and reliever (rescue) medications [2]. Controller medications, such as inhaled corticosteroids (ICS) and long-acting beta-adrenoceptor agonists (LABA), are used for regular maintenance treatment [24–26]. These medications reduce airway inflammation, control symptoms, and reduce future risks, such as exacerbations and decreased lung function. Reliever medications, such as short-acting beta-2-adrenoceptor agonists (SABA), are provided to all patients for asneeded relief of breakthrough symptoms, including during worsening of asthma or exacer‐ bations [24–26]. They are also recommended for short-term prevention of exercise-induced bronchoconstriction [2]. Reducing and, ideally, eliminating the need for reliever treatment are both an important goal in asthma management and a measure of the success of asthma treatment. Add-on therapies for patients with severe asthma may be considered when patients have persistent symptoms and/or exacerbations, despite optimized treatment with high-dose controller medications (usually a high-dose ICS and a LABA) and treatment of modifiable risk factors [2].

The initiation of asthma therapy in a stable patient who is not already receiving medications is based upon the severity of asthma in the individual. Patients with mild intermittent asthma are best treated with an inhaled SABA, which should be taken as needed for the relief of symptoms [2]. Patients in whom triggering of asthmatic symptoms can be predicted (e.g., exercise-induced bronchoconstriction) are encouraged to use their inhaled beta agonist approximately 10 min prior to exposure, to prevent the onset of symptoms [2]. For mild persistent asthma, the preferred long-term controller is a low-dose ICS [2]. Regular use of ICS reduces the frequency of symptoms (and the need for SABAs for symptom relief), improves the overall quality of life, and decreases the risk of serious exacerbations [2]. Alternative strategies for treatment of mild persistent asthma include leukotriene receptor antagonists, theophylline, and cromoglycate [2, 26].

For moderate persistent asthma, the preferred therapy is low doses of ICS plus an inhaled LABA, or medium doses of ICS [2]. Alternative strategies include adding a leukotriene modifier (leukotriene receptor antagonist or lipoxygenase inhibitor) or theophylline to lowdose ICS [2]. For severe persistent asthma, the preferred treatments are medium (Step 4) or high (Step 5) doses of ICS, in combination with an inhaled LABA [2]. In addition, for patients who are inadequately controlled on high-dose ICS and LABAs, the anti-IgE therapy omalizu‐ mab may be considered, if there is objective evidence of sensitivity to a perennial allergen (by allergy skin tests or in vitro measurements of allergen-specific IgE) and if the serum IgE level is within the established target range [2].
