A prospective, randomized, open, multi-centre study to assess safety of PURETHAL Birch given with a rush up-dosing regimen to patients with allergic rhinitis/rhinoconjunctivitis.

The aim of the study is to show that reaching the maintenance dose of 0.5 ml PURETHAL Birch following a rush regimen of three injections in weekly intervals is as safe as a conventional regimen of six injections in weekly intervals.