Background
Probiotics have been associated with prevention and improvement of symptoms in atopic diseases such as atopic dermatitis. However, few studies exist that document their efficacy for upper airways allergies such as allergic rhinitis.
Methods
Thirty-one adult volunteers with allergic rhinitis were enrolled in a randomized, double-blind, placebo-controlled study, based on two 4-week cross-over periods of product consumption (ST11-fermented milk vs. placebo), separated by a wash-out period of 6-8 weeks. Objective and subjective clinical parameters of NPT as well as systemic and nasal immunological parameters were compared between the two treatment periods (registration number: NCT 011 50 253).
Objective
To investigate the effect of short-term oral administration of Lactobacillus paracasei ST11 on a nasal provocation test (NPT) with grass pollen.
Results
Subjects that received ST11-fermented milk had lower nasal congestion than subjects under placebo (visual analogical scale; P<0.05). Nasal pruritus followed the same trend. However, no significant change in combined nasal reaction threshold was observed between the two periods. IL-5 secretion by peripheral blood mononuclear cells and serum allergen-specific IgG4 were significantly lower in ST11-fermented milk group compared to placebo group. IL-8 and IL-10 secretion followed the same trend.
Trial registration
ClinicalTrials.gov NCT01150253.