Specific Hyposensitization and Neurotropin Therapy for Perennial Allergic Rhinitis.

Neurotropin®, an extract isolated from inflamed rabbit skin, has been used in Japan as an anti-allergic. We studied the effectiveness of the combined treatment of hyposensitization and Neurotropin® injections on perennial allergic rhinitis. Assessment was based on clinical effectiveness and changes in the serum levels of specific IgG, IgG1 and IgG4 antibodies against house dust mite in a multicenter well-controlled study. The control group was treated with specific hyposensitization alone.In the combined treatment (CT) group, house dust hyposensitization therapy and Neurotropin® in a dose of 3ml were administered simultaneously twice a week for 12 to 36 weeks. The number of patients treated for 12 weeks or more was 72 in the single treatment (ST) group and 68 in the CT group. The global improvement rating, determined by both subjective symptoms and objective examinations, of the CT group (88.2% of cases; improvement or better) was significantly superior to that of the ST group (66.2%). Among the subjective and objective findings observed, the improvement of disturbance in daily life, swelling of the inferior nasal concha, and the amount of nasal secretion in the CT group was significantly greater than the improvement in the ST group. No significant difference was observed in the frequency of side effects, including drop-outs, between the ST group (4 out of 73) and the CT group (5 out of 69). The effectiveness of treatment in the CT group was significantly greater than in the ST group, with more “remarkable improvement” cases being found in the CT group. However, Dermatophagoides pteronysis-specific IgG (s-IgG), s-IgG1 and s-IgG4 antibody levels did not differ significantly between the two groups, although they were somewhat higher after than before treatment. For both groups, no remarkable difference was found in changes in s-IgG, s-IgG1 and s-IgG4 antibody levels between those showing clinical effectiveness and those without a good response.The results indicate that Neurotropine treatment combined with hyposensitization was more beneficial than hyposensitization alone, but we failed to reveal whether or not Neurotropin® affects the mechanism by which hyposensitization therapy works.