EFFECT OF MULTISTRAIN PROBIOTICS ON THE SEVERITY AND FREQUENCY OF UPPER RESPIRATORY TRACT INFECTIONS: A CLINICAL STUDY

Abstract

Background: Upper respiratory tract infections (URTIs) are a common health issue that significantly impact individuals’ quality of life. Probiotic supplementation has been suggested as a potential intervention to reduce the frequency, severity, and duration of URTIs.

Objective: This study aimed to evaluate the role of multistrain probiotics in the prevention and management of URTIs.

Methods: This cross-sectional study was conducted at Multiple Teaching Hospitals of Punjab, Pakistan During December 2025 till February 2026. The study involved a total of 185 patients, aged between 18 and 65 years. Data collection was carried out in two phases: baseline and follow-up. At baseline, participants underwent a thorough medical examination and completed questionnaires assessing their general health and history of respiratory infections.

 Results: The treatment group experienced a significantly lower frequency of URTIs (1.14 episodes per participant) compared to the placebo group (2.03 episodes per participant, p < 0.01). Symptom severity, as indicated by the Jackson score, was significantly reduced in the probiotic group (2.3 ± 0.8) compared to the placebo group (3.4 ± 1.1, p < 0.05). The duration of illness was also shorter in the treatment group (4.5 ± 1.2 days) compared to the placebo group (6.2 ± 1.5 days, p < 0.01). Immune markers showed a favorable response in the probiotic group, with a reduction in IL-6 levels and an increase in IL-10. 

Conclusions: Multistrain probiotics significantly reduce the frequency, severity, and duration of URTIs. The probiotics also positively impact immune function and quality of life, with minimal side effects. These findings suggest that multistrain probiotics could be a useful adjunct in the prevention and management of URTIs, particularly in individuals prone to recurrent infections.