Safety of rush immunotherapy using a modified schedule: A cumulative experience of 893 patients receiving multiple aeroallergens

Conventional immunotherapy (IT) is effective in treating allergic rhinitis, allergic asthma, and chronic rhinosinusitis. Disadvantages include poor compliance, delayed efficacy, and patient frustration. Rush IT, or rapid desensitization, offers the advantages of rapid response, improved compliance, and cost-effectiveness. Although premedication with corticosteroids and antihistamines dramatically reduces systemic reactions, safety remains a primary concern. Two separate half-day schedules with minor differences were used to rapidly desensitize 893 patients (aged 1.5–77 years) in two typical outpatient settings equipped to treat anaphylaxis. All patients exhibited positive skin-prick tests to perennial and seasonal allergens. Diagnoses included allergic rhinitis (857/96%), allergic asthma (505/57%), and chronic rhinosinusitis (384/43%). Five hundred sixty-eight patients were premedicated with prednisone and H1-antihistamine for 3 days. Three hundred twenty-five patients were premedicated for 3 days with prednisone and H1- and H2-blockade. The protocol's final dose ranged from 0.1 to 0.5 mL of a 1:1000 dilution of extracts manufactured by ALK and Greer Laboratories. Patients continued on to higher doses by resuming a conventional schedule. Eighteen patients (2.0%) experienced a mild systemic reaction. All responded to subcutaneous epinephrine and/or nebulized albuterol and were sent home after observation. One patient (0.1%) experienced true anaphylaxis and received appropriate treatment and observation. Our experience with rush IT confirms that maintenance IT can be reached quickly and safely under careful supervision. Caution must be exercised when using this procedure because anaphylaxis does occur. Systemic reactions occur less frequently using a lower targeted final dose than previously described in the literature.