The investigators performed open-labeled pilot study which evaluates the efficacy and safety of allergen-specific intralymphatic immunotherapy (ILIT) for allergens including Dermatophagoides farinae (Df), Dermatophagoides pteronyssinus (Dp), cat, and dog that are sensitized and provoke rhinitis-related symptoms in patients with allergic rhinitis.

After informed consent, causal allergen was injected into inguinal lymph node through guidance by ultrasonography three times with 4-week interval. Initial dose of allergen was 1,000-fold diluted solution from maximal concentration of allergen extract for subcutaneous immunotherapy (30 AU/ml for Df or Dp, 10 AU/ml for Cat hair, and 1:1/10 weight/volume for dog hair/dander, HollisterStier, New Orleans, USA) in volume of 0.1ml. After the first dose, allergen concentration was escalated 3-fold at second dose, and 10-fold at third dose if there was no or mild local or systemic hypersensitivity reaction. The allergen concentration did not change at second or third dose if there was moderate local or systemic reaction. The allergen concentration was decreased by 10 or 100-fold from previous concentration if there was severe local or systemic reaction.

The investigators evaluated parameters regarding allergic rhinitis within a week before the first injection and 4 months after the first injection. These parameters included Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ) and Sino-Nasal Outcome Test (SNOT-20), and Visual analogue scale (VAS) of symptoms including rhinorrhea, sneezing, nasal obstruction, postnasal drip, eye/nose/ear/palate itching, dyspnea, wheezing, chest discomfort as well as urticaria, angioedema, and itching on exposed skin during exposure to causal allergen in daily life. Skin prick test, intradermal test, blood sampling for serum allergen-specific IgE, exhaled nitric oxide, and nasal lavage for Th1, Th2, and Treg cytokines were also included. Adverse events were recorded and graded according to Muller's classification and Ring and Messmer's classification.

Inclusion Criteria:

• Allergic rhinitis to house dust mite (Df, Dp), cat or dog
• More than 3mm reaction at skin prick test for Df, Dp, cat or dog or more than class 3 at serum specific IgE level (UNICAP or MAST)

Exclusion Criteria:

• Uncontrolled or severe asthma according to Global Initiative of Asthma (GINA) guideline
• FEV1 less than 50% of predicted value if there is comorbid asthma
• Subject rejects the enrollment into study
• Low compliance
• Pregnancy or lactation
• Significant cardiovascular, hepatic, renal, hematologic, oncologic, or infectious diseases
• Administration of beta blocker, angiotensin converting enzyme inhibitor, tricyclic antidepressant, immunosuppressant including systemic glucocorticosteroid (20mg or more dose of prednisolone or equivalent dose of other steroid) within last 2 weeks
• Prior history of allergen-specific immunotherapy
• Allergic rhinitis caused by other perennial or seasonal allergen
• Vulnerable volunteer