The study aimed at determining selected immunologic parameters of the cellular histamine secretion and skin reactivity in the group of 9 patients hypersensitive to insect poison with effective immunotherapy following 2 years of maintenance treatment. It has been shown that the continuation of the specific immunotherapy for 2 years maintains and even increases favourable changes in humoral and cellular immunity induced already in the early phase of desensitization. An assay of the specific IgE and IgG4, cellular histamine secretion, and skin reactivity is of value in monitoring specific allergy to insect poison immunotherapy.