[Short-term immunotherapy--a survey of current studies]

Immunotherapy (IT) plays a central role in the therapy of allergic rhinitis as it was proved to be causal and preventive. IT induces humoral and cellular changes in the immune system, a reduction of symptoms and a prophylactic effect regarding a possible expansion of the allergene spectrum and of involved organ systems. Regular therapeutic schedules include allergen injections starting immediately after the pollen season and ending just before the expected beginning of a season. Additionally, perseasonal and perennial therapy schemes have been used. In all these, a phase of dose-increase is followed by an individually adjusted steady-state preservation-phase. In perseasonal and perennial scheme the injections are given during the pollen season. The preseasonal shortterm-immunotherapy is another schedule. The increase of the injected allergen-dose is made very fast (most commonly during seven weeks), so that the phase of dose-increase is shortened considerably, and a preservation-phase does not take place. This shortterm-immunotherapy has been developed for patients who consult their doctor shortly before the start of the pollen season. The preseasonal shortterm-immunotherapy has been shown to be efficient regarding allergic rhinitis caused by grass-, rye-, birch-, hazel- and alder-pollen. Clinical and experimental data of two placebo-controlled trials and one open study are presented and the role of this new immunotherapy approach is discussed.