Safety of Venom Immunotherapy in Patients Pretreated with Antihistamines—A Retrospective Study

Imrnunotherapy is the only effective method of treatment of allergy to Hymenoptera venom. Pretreat­ment with antihistamines diminishes the incidence of adverse reactions (AR) such as large local and mild systemic reactions but it is suggested that it may mask a development of serious allergic reactions. The aim of the study was a retrospective evaluation of the incidence and nature of AR during venom immuno­therapy in patients receiving pretreatment with antihistamines in the Department of Pneumonology and Allergy of the Medical University of Lodz. Results: 50 patients started “ultra-rush” immunotherapy in our center, 8 were taken in our care after the initiation phase had been conducted elsewhere. During the dose increase phase IO systemic adverse reactions were observed. 50% of them were only subjective and the rest mild objective reactions. During the maintenance phase IO systemic reactions were noted, among them 2 cases of the anaphylactic shock. The incidence of systemic adverse reactions was I per 86 injections. Late as well as unusual reactions appeared twice. Conclusions: Venom immunotherapy combined with pretreatment with antihistamines is safe. A vast majority of systemic adverse reactions is of subjective and mild objective nature and appropriate treatment leads to contain­ment of severe reactions.