Research · Systematic review
Probiotics for preventing acute upper respiratory tract infections
What it found
Probiotics reduced the proportion of people with at least one acute URTI (RR 0.76) and cut antibiotic use and mean episode duration (~1 day) — though most estimates are low-to-moderate certainty and no formulation can be recommended.
- Design
- Systematic review
- Year
- 2022
- Sample size
- 6,950
- Population
- children, adults, and older adults (23 RCTs analyzed)
- Intervention
- various probiotic strains (mostly Lactobacillus/Bifidobacterium) vs placebo
- Outcome
- acute URTI episodes, episode duration, antibiotic use
- Journal
- Cochrane Database of Systematic Reviews
Citation last checked 2026-06-21.