To assess the effectiveness of the Buteyko method as an adjunct therapy in the treatment of asthmatic children with mouth breathing.

Inclusion Criteria:

• Children from 7 up to 12 years old with asthma diagnose
• Regular inhaled corticosteroids with no change in dose in the preceding 4 weeks.
• Children cannot present: other respiratory disease (such as cystic fibrosis, bronchiectasis, and tuberculosis), retinal detachment, hypertensive crisis, congenital heart defect, pulmonary edema, history of lobectomy or lung segmentectomy, respiratory infections 15 days prior to the evaluations.

Exclusion Criteria:

• Children that are not able to perform some of the necessary procedures, give up participating in the research and present acute symptoms of respiratory tract during the assessments.