NutriStack
D-Mannose and Saccharomyces Boulardii, a synergy.
D-Mannose and the probiotic yeast Saccharomyces boulardii have been combined as a non-antibiotic UTI prophylaxis strategy. A randomized pilot study gave D-Mannose 500 mg plus S. boulardii 3 billion CFU after cystoscopy and reported lower post-procedure UTI incidence and less urinary discomfort versus no treatment. The pairing is mechanistically rational because the two ingredients target distinct steps (urinary bacterial anti-adhesion and flora restoration) and there is no absorption or pharmacological conflict between a poorly metabolized sugar and a transient gut-colonizing yeast.
One pair, every claim cited. The two substances, the type, the mechanism, the recommendation, and the primary literature.
Same shape as the other 1,729 pairs in the public database.
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At a glance
- Substances
- D-Mannose and Saccharomyces Boulardii
- Pair type
- Synergy
- Evidence (highest tier)
- Emerging
- Source citations
- 2 sources
- Stack Score effect
- +2 to your Stack Score (per scored synergy row).
- Scope
- Supplement × Supplement
- Last verified
- May 30, 2026
Synergy · Emerging evidence
Synergy
What is happening. D-Mannose and the probiotic yeast Saccharomyces boulardii have been combined as a non-antibiotic UTI prophylaxis strategy. A randomized pilot study gave D-Mannose 500 mg plus S. boulardii 3 billion CFU after cystoscopy and reported lower post-procedure UTI incidence and less urinary discomfort versus no treatment. The pairing is mechanistically rational because the two ingredients target distinct steps (urinary bacterial anti-adhesion and flora restoration) and there is no absorption or pharmacological conflict between a poorly metabolized sugar and a transient gut-colonizing yeast.
Mechanism. Complementary anti-uropathogen actions. D-Mannose saturates FimH adhesins on type 1 fimbriated E. coli, preventing the bacteria from anchoring to bladder uroepithelium so they are flushed out in urine. Saccharomyces boulardii is a probiotic yeast that supports colonization resistance and modulates gut and urogenital flora that seed recurrent urinary tract infections. The two act on different points of the infection pathway (direct urinary anti-adhesion plus restoration of protective commensal flora) rather than competing.
Recommendation. Reasonable to combine for recurrent UTI prophylaxis. Typical regimens use D-Mannose 1.5 to 2 g once or twice daily with S. boulardii 250 to 500 mg (roughly 3 to 10 billion CFU) daily. No timing separation is required; both can be taken together. Maintain hydration to support urinary flushing. People who are critically ill, immunocompromised, or have a central venous catheter should avoid live S. boulardii because of a rare risk of fungemia.
Minimum separation. None required; may be taken together
Sources (2)
- Prospective randomized pilot study of D-mannose plus Saccharomyces boulardii to prevent urinary tract infections and discomfort after cystoscopy, urology literature (2023)
- Reviews on non-antibiotic prophylaxis of recurrent uncomplicated cystitis describing D-mannose combined with probiotics, urology and nutraceutical literature
Stack Score
How this pair moves the number.
Effect on the composite score
If both D-Mannose and Saccharomyces Boulardii are in the same stack, this pair applies +2 to your Stack Score (per scored synergy row).
The full algorithm, the clamping rules, and four worked stacks are documented at /methodology/stack-score.
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