This prospective open multi-centre non-interventional study initiated to document the up-dosing period of children and adults with allergic rhinoconjunctivitis and/or allergic asthma treated with a SLIT containing purified, aqueous extracts of birch, alder, and hazel pollen. The following up-dosing schemes are freely selectable: scheme A consists of an up-dosing period of 12 days at the patient´s home using the standardized pollen extract in three different solution strengths to reach the maximum dose; scheme B is performed only with the highest solution strength at the physician's office within 2 hours; and the new scheme C which is a regimen for initiation at the physician's office and continuation at the patient's home also exclusively using the highest solution strength and takes 4 days. Data are documented by physicians and in patients´ diaries.

Inclusion Criteria:

• Patients of the age of 2 years and older suffering from a tree pollen induced seasonal allergic rhinitis

Exclusion Criteria:

• Patients suffering from acute or chronic infections or inflammations
• Patients suffering from secondary modifications of the target organ with function impairment (emphysema, bronchiectasis)
• Patients suffering from severe and uncontrolled asthma
• Patients with a known severe autoimmune disease
• Patients with active malignant disease
• Patients requiring beta-blockers
• Patients having any contraindication for the use of adrenaline
• Patients with a hypersensitivity to the excipients of the drug

Adults, adolescents and children from the age of 2 on, who suffer from seasonal allergic rhinoconjunctivitis causued by tree pollen.