We treated 14 patients with severe pollinosis or allergic rhinitis with its specific allergen by the sublingual route. Increasing doses of the allergen were given as drops. There was marked improvement in allergic symptoms in 12. Sneezing, itching of the eyes and rhinitis were practically absent, even in the season and there was substantial reduction in intake of antihistamines as well as in the use of steroid inhalers. Only 1 patient did not improve, while 1 developed severe urticaria to Parietaria judaica vaccine.