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3Medicinal

D-mannose

Also sold as Mannose

A simple sugar sold to prevent recurrent urinary tract infections — early trials were encouraging, but a larger 2024 trial found no benefit.

TrustedSupp Tier System™ · Tier 3Take as a defined course

Evidence strength

28/100Weak
WEAKLIMITEDMODERATESTRONGVERY STRONG

What the evidence supports: UTI prevention — early small trials were positive, a larger 2024 trial was not.

This scores how well-supported the claim above is — not how much benefit you personally would get. A high score on a narrow claim does not extend to everything the product is marketed for.

How long to take it

Ongoing for prevention if used — but the best-quality evidence now questions its benefit.

Who it's actually for

Women with recurrent UTIs exploring options, with realistic expectations.

Safe upper limit

Unverified
No formal upper limit; 2 g daily is the common prevention dose
Generally well tolerated; loose stools at higher doses. It is a sugar, though with little effect on blood glucose at typical doses.
No source or citation attached yet.

Interactions to know about

No commonly documented medication clashes in our data. That is not the same as none existing.

Run your full list through the interaction check.

Practical notes

  • An active UTI needs medical treatment — this is not a treatment.
  • A large 2024 randomised trial in primary care found no reduction in recurrence.
  • Cranberry PACs have somewhat more consistent evidence for prevention.