Local intranasal immunotherapy with high-dose polymerized ragweed extract

Thirty-one ragweed-allergic patients received preseasonal local intranasal immunotherapy (LNIT) with high doses of gluteraldehyde-polymerized ragweed extract (average total dose 544 micrograms antigen E). Minimal side effects were reported during treatment and did not interfere with the dosing schedule. During the ragweed pollen season, LNIT-treated patients had lower symptom scores for sneezing, rhinorrhea and nasal congestion than a comparable group of untreated ragweed-allergic patients. There was no difference in ragweed-induced eye symptoms between the two groups. Secretory ragweed-specific IgA and IgG rose following LNIT treatment. Absolute antibody titers and changes in titers did not correlate with clinical improvement. LNIT with the polymerized ragweed did not block the seasonal rise in serum ragweed-specific IgE. These results suggest that LNIT with high-dose polymerized ragweed extract is a safe, simple and effective form of immunotherapy.