The aim of the study is to assess the safety and efficacy of sublingual immunotherapy applied preseasonal and seasonal in ultra-rush scheme in children with bronchial asthma allergic to grass pollen. The investigators will assess clinical symptoms, reliever drugs usage, lung function, chosen markers of allergic inflammation, bronchial hyperreactivity with methacholine, and presence and type of allergy after two years of sublingual immunotherapy (SLIT) in children with asthma.

Specific immunotherapy is the only causal treatment method of atopic diseases including bronchial asthma in children. Sublingual immunotherapy seems to be the most promising alternative to traditional specific subcutaneous injection immunotherapy.

The aim of the study is to assess the safety and efficacy of sublingual immunotherapy applied preseasonal and seasonal in ultra-rush scheme in children with bronchial asthma allergic to grass pollen. We will assess clinical symptoms, reliever drugs usage, lung function, chosen markers of allergic inflammation, bronchial hyperreactivity with methacholine, and presence and type of allergy after two years of SLIT in children with asthma.

After two years the study will be unblinded, all the children will be given grass pollen allergen extract for a year.

Inclusion Criteria:

• patients allergic to grasses pollen
• patients with bronchial asthma
• patients with controlled asthma
• patients who were qualified for immunotherapy and gave written informed consent for immunotherapy

Exclusion Criteria:

• patients allergic for other perennial and seasonal allergens
• patients with other chronic diseases 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