The purpose of the current study is to evaluate the efficacy of administering a multistrain probiotic in adult human subjects suffering from allergic rhinitis and evaluate both symptomatology through validated questionnaires and gut microbiota modification during and after treatment.

Adult subjects (18-60) with documented allergic rhinitis will be assigned to placebo or probiotic groups and take either placebo or probiotic dietary intervention for 8 weeks. Total nasal symptom score (TNSS), Rhinitis Control Assessment Test (RCAT), Mini Rhinoconjunctivitis Quality of Life Questionnaire (MiniRQLQ) will be compared over 12 weeks between the two treatment groups. In addition, serological markers (Eosinophil count, Total IgE and Eosinophilic cationic protein) and gut microbiota features will be evaluated over a 12 week period.

Inclusion Criteria:

• Adults aged 18 to 65 years of age
• Established allergic rhinitis (clinical history of rhinorrhea, congestion, sneezing, pruritis >2 years)
• Positive Skin Prick Test and/or Specific IgE to at least one aeroallergen.
• Have signed the consent form
• Have been instructed during screening and agreed to not take any probiotic containing products outside the study for the study period

Exclusion Criteria:

• Subjects currently under treatment with antibiotics
• Subjects undergoing allergen immunotherapy
• Pregnancy
• Vasomotor rhinitis
• Nasal cavity disorders
• Ear infections
• Other chronic diseases (e.g. gastrointestinal, cardiovascular, infections)
• Subjects diagnosed with non-controlled asthma
• Subjects currently participating in another interventional clinical trial or having participated in another clinical trial in the last 2 months
• Subjects on chronic use of systemic corticosteroids
• Proton pump inhibitors 2-weeks prior to randomization
• Antibiotics 2-weeks prior to randomization