Dosage is For adults: One 300-IR (index of reactivity) tablet of the 5-grass pollen extract (Oralair®) or one 2800-BAU (bioequivalent allergy unit) tablet of the timothy grass extract (Grastek®) taken once a day For patients aged 5 to 17 years: One 100-IR tablet of the 5-grass pollen extract on day 1, two 100-IR tablets simultaneously on day 2, then one 300-IR tablet once a day from day 3 onward For patients aged ≥ 5 years with grass pollen-induced allergic rhinitis: One 2800-BAU tablet of the timothy grass pollen extract taken once a day The first dose is given in a health care setting and patients should be observed for 30 minutes after administration because anaphylaxis may occur.