Immunotherapy for nasal allergy.

Controlled studies establish the effectiveness of immunotherapy for allergic rhinitis related to grasses, ragweed, mountain cedar, and birch pollens. Clinical improvement appears to be specific, to require adequate dosage, and to relapse once booster injections are discontinued. Specific immunologic responses increase blocking IgG antibodies in serum and secretions, blunt IgE responses, and reduce lymphocyte reactions. Immediate mediator release is reduced both in basophils challenged in vitro and in nasal secretions after local challenge in vivo. Effects on late-phase inflammatory reactions are still under investigation. Standardization of allergenic extracts by immunologic methods should make useful therapeutic responses more frequent.