The present study was conducted to determine the effects of four week treatment with budesonide, montelukast, budesonide with montelukast and budesonide with formoterol in children with atopic asthma on lung function: forced expiratory volume in one second, mid-expiratory flow, peak expiratory flow rate, resistance by the interrupter technique, plethysmographic specific airway resistance, exercise-induced bronchial hyperreactivity and clinical symptoms.

Asthma is one of the most common chronic disease worldwide, imposing a substantial social burden on children. Allergic inflammation is responsible for all clinical symptoms of asthma. The effects of allergic inflammation are: bronchial muscle constriction, excessive mucus production, and edema of mucosa, all elements of "asthmatic triad" causing bronchial obturation. Normal lung function is one of the goals of asthma management. In most of the studies the effect of monotherapy on the symptom scores, lung function parameters and bronchial hyperreactivity was assessed.

The present study was conducted to determine the effects of four week treatment with budesonide, montelukast, budesonide with montelukast and budesonide with formoterol in children with atopic asthma on lung function: forced expiratory volume in one second, mid-expiratory flow, peak expiratory flow rate, resistance by the interrupter technique, plethysmographic specific airway resistance, exercise-induced bronchial hyperreactivity and clinical symptoms.

Inclusion Criteria:

• Male and female outpatients
• Aged 6 to 18 with a clinical diagnosis of bronchial asthma with a duration of at least 6 months before the first visit and with current history of moderate persistent asthma
• Sensitive to house dust mites as shown by positive skin-prick tests to Dermatophagoides pteronyssinus or Dermatophagoides farinae
• To become eligible for the active treatment period, patients and their parents were required to do reproducible spirometry, whole body plethysmography and interrupter technique.
• In order to be included in the study the patients had to have a resting FEV1 of more or equal 70%.

Exclusion Criteria:

Study exclusions included:

• Active upper respiratory tract infection within 3 weeks before the study and acute sinus disease requiring antibiotic treatment within 1 month before the study
• Previous intubation
• Asthma hospitalisation during the 3 months before the first visit.
• Additional criteria were other clinically significant pulmonary, hematologic, hepatic, gastrointestinal, renal, endocrine, neurologic, cardiovascular, and/or psychiatric diseases or malignancy that either put the patient at risk when participating in the study or could influence the results of the study or the patient's ability to participate in the study as judged by the investigator.
• Excluded medications were β-blockers (eye drops included), astemizole within 3 months, or oral corticosteroids within 1 month before the first visit.
• Patients who were receiving immunotherapy were also excluded.