The so far most comprehensive individual study into the clinical findings in the hyposensitization therapy with pollen-L-tyrosine complexes in 253 pollinosis patients, who were first subjected to a hyposensitization therapy, permitted a comprehensive evaluation of the indication possibilities of these preparations (Pollagen, Tyrosin-Allergoid; in other countries available as Pollinex, Polvac, Bencard-Polen). The success of this hyposensitization, which may be reduced to three injections, can be immunologically established and is only slightly smaller than in the case of a specific desensitization over a period of 5--6 months preseasonally. The therapy is indicated first and foremost in patients who either have a moderate or medium-degree sensitization to grass pollens or who come to a medical examination only briefly before the pollen season. The addition of rye pollens obviously gives the preparation Tyrosin-Allergoid an advantage over the mixture of pure grass pollens as used in Pollagen. Rye pollens are responsible for the highest pollen concentrations and thus for the most severe complaints of pollinosis patients. A considerable increase in the therapeutic success, approximately 20%, can be achieved on the basis of a therapy modification, presented here for the first time: The patient is treated preseasonally with a specific desensitization vaccine and immediately before the pollen season he is additionally vaccinated with tyrosine-adsorbed pollen allergens as a kind of booster vaccination.