Probiotics for Sustained Health

This randomized, double-blind, placebo-controlled pilot study will evaluate the effect of a probiotic supplement on upper respiratory tract infections (URTIs) in children aged 4-18 years with a history of recurrent URTIs. Participants will be randomized to receive either probiotic drops or placebo drops. The primary objective is to assess the effect of the probiotic on the frequency of URTI episodes during the study period. Secondary objectives include evaluation of respiratory symptoms, medication use, healthcare visits, school absenteeism, recovery of the administered probiotic, and safety.

Inclusion Criteria: * Age 4 to18 years * Male or female * Healthy (no known chronic disease) * At least 3 episodes of Upper Respiratory Tract Infection (pharyngitis and or tonsillitis, cold, rhinitis, sinusitis) in the previous year * Written informed consent signed by both parents or caregivers Exclusion Criteria: * Use of antibiotics or probiotic products 2 weeks prior inclusion in the study * Use of two or more consecutive months on antibiotics for respiratory infections on the last year * Participation in another clinical trial * Parents or caregivers unable to read, understand and follow the instructions