Venom immunotherapy: comparison of "rush" vs "conventional" schedules

Twenty-three patients aged five to 52 years with good clinical histories of severe systemic reactions to hymenoptera stings confirmed by skin tests and RAST levels were treated with specific insect venoms. A more conventional, slow, bi-weekly schedule was used to determine whether they could be as successfully treated as those in earlier studies employing the "Rush desensitization" approach. It was also hoped these subjects would experience fewer untoward reactions. Comparisons of IgG (anti-hyaluronidase and phospholipase) levels pretreatment and after top dose (100 mcg) in all cases showed greater than three-fold rise, indicating protection. RAST IgE rose in most cases and plateaued by six months. Nineteen patients were restung to verify protection. Untoward reactions to injections were low (13%) and easily controlled. The authors conclude that the use of specific freeze dried insect venoms in a slow dose schedule is safe and effective in protecting severely sensitized individuals.