Compound or practice · Supplement
Cranberry
Genuinely reduces recurrent UTIs via proanthocyanidins — prevention, not treatment.
- Overall grade
- Grade B
- Last revised
- 2
- graded outcomes
- 0
- references listed
A structured monograph in Prometheus's bundled library. Its grades are the monograph's own reading of the evidence, not a peer-reviewed review.
2 at grade B · 1 at grade D — 3 graded rows
What is known
Each outcome with its grade (how strong the evidence is, A to D), the size of the effect where the entry records one, and how often studies agree.
- Recurrent UTI preventionEvidence grade B
In susceptible groups
Moderatemixed
- Active UTI treatmentEvidence grade D
Not a treatment
Trivialhigh
Conditions
How the entry reads its effect on diagnosed conditions: the direction first, then the grade. Never a substitute for the person who treats you.
- Recurrent urinary-tract infection May improveEvidence grade BPreventionGrade B
What is uncertain
Read off the same rows as above. Nothing here is added that the entry does not itself record.
- Thin evidence: Active UTI treatment (grade D).
- Studies disagree: Recurrent UTI prevention (mixed agreement).
Interactions
Documented pairings with supplements and medicines. A medicine on this list is a conversation for whoever prescribes it.
D-MannoseWorks together
Both target E. coli adhesion — common UTI-prevention pairing.
The evidence in words
What it is
Cranberry (proanthocyanidin-standardized extract or juice) is used to prevent urinary-tract infections.
How it works
Its A-type proanthocyanidins stop E. coli from adhering to the bladder wall, reducing colonization.
What the evidence shows
Updated Cochrane evidence supports cranberry for reducing recurrent UTIs in susceptible people (women with recurrent UTIs, some others); it does not treat an active infection. Standardized PAC content matters more than juice volume.
How to use it
Products standardized to ~36 mg proanthocyanidins daily for prevention.
Safety & interactions
Safe; juice carries sugar; theoretical mild warfarin interaction at high intake. D-Mannose — Both target E. coli adhesion — common UTI-prevention pairing.
Bottom line
A legitimate UTI-prevention tool (not a treatment) if you get recurrent infections. Dose by PAC content, not juice.
How it is used
As the entry records it, from the studies it summarises. Not a recommendation for you — doses that suit a trial population may not suit you.
- Standard
- ~36 mg proanthocyanidins/day.
Goes with
- D-MannoseBoth target E. coli adhesion — common UTI-prevention pairing.Evidence grade C
Related reading
Entries that share this one's tags or conditions.
- Cranberry for Active UTI treatmentEvidence grade D — Not a treatmentEvidence grade D
- Cranberry for Recurrent urinary-tract infectionEvidence grade B — PreventionEvidence grade B
- Cranberry for Recurrent UTI preventionEvidence grade B — In susceptible groupsEvidence grade B
- Cranberry: dosage and how to take it~36 mg proanthocyanidins/day.Evidence grade B
Sources
This entry lists no references of its own.
Last revised . A grade is this entry's reading of the evidence, not medical advice.