We studied 97 consecutive patients who had received Hymenoptera venom rush immunotherapy in our department. There were 53 males and 44 females, whose mean age was 46 years (8–74 years). Most study patients had experienced severe anaphylaxis induced by a Hymenoptera sting: the reaction was Müller stage IV in 48 patients. Skin tests were positive for Vespula venom in 85 cases, Polistes venom in 23, and bee venom in 23. Radioallergosorbent test values exceeded 0.70 kIU/1 in 60 cases. Immunotherapy was performed with Vespula venom alone in 73 cases, bee venom alone in five cases, and both Vespula and bee venom in 19 cases. A cutaneous reaction was seen at the injection site in most patients. Four patients also had skin manifestations in areas remote from the injection site. Blood pressure elevation was seen in 11 patients, moderate hypotension in two, rhinitis in one, asthenia or headache in seven, visual disorders and vertigo in two, and transient dyspnea in two. Our protocol has proved very safe, epinephrine never being required in the 97 reported cases.