Awaiting clinical review. This entry is sourced but has not yet been signed off by a pharmacist or clinician.
Cranberry
Cranberry probably reduces the number of recurrent urinary tract infections in women with a history of them and in children, but it is not a treatment for an infection you already have. The 2023 Cochrane review found a moderate-certainty 26% relative reduction in women with recurrent UTIs, though the trials disagreed with each other and the products and doses varied. If you take warfarin, UK regulators and the NHS advise avoiding cranberry products.
At a glance
Last reviewed 29 September 2026What it's used for
Evidence is rated per use. The same ingredient can be strong for one thing and traditional for another.
| Use | Evidence | What the research shows |
|---|---|---|
| Preventing recurrent UTIs in women | Moderate | In the 2023 Cochrane review (8 trials, 1,555 women with recurrent UTIs), cranberry probably reduced symptomatic, culture-confirmed UTIs (risk ratio 0.74, 95% CI 0.55 to 0.99; I² 54%, so trials were inconsistent). A later placebo-controlled trial of 160 Greek women with recurrent cystitis, taking a 240 mg capsule daily for 12 months, reported about half as many UTIs (incidence rate ratio 0.49). NCCIH says the effect is still in question because findings are inconsistent. We rate it 3, not 4, because the confidence interval nearly reaches 1 and the trials used different products.1,3,4 |
| Preventing UTIs in children | Moderate | The Cochrane review pooled 5 trials in 504 children and found fewer symptomatic, culture-verified UTIs (risk ratio 0.46, 95% CI 0.32 to 0.68). The trials are small in number and the review does not show which product or dose works best.1 |
| Preventing UTIs after urinary procedures | Moderate | In people made susceptible to UTIs by a medical intervention (6 trials, 1,434 people), the review found a risk ratio of 0.47 (95% CI 0.37 to 0.61). This group is defined by the review as people at risk because of an intervention such as surgery or catheterisation; we did not read the individual trials.1 |
| No benefit shown: older people in care, pregnancy, bladder-emptying problems | Limited | Cochrane found little or no benefit in institutionalised older adults (3 trials, 1,489 people, RR 0.93), pregnant women (3 trials, 765, RR 1.06) and adults with neuromuscular bladder dysfunction (3 trials, 464, RR 0.97), and concluded the evidence does not support use in these groups.1 |
| Treating an active UTI | Traditional | A 2023 Cochrane review of cranberry for treatment found no randomised trials that met its criteria, so there is no good-quality evidence it works. NCCIH says it is not recommended as a treatment in any population, and the NHS says there is no evidence it eases symptoms once an infection has started.2,4,5 |
How much
Ranges below are what studies used and what supplements commonly contain. They are not a recommendation for you. Start at the low end.
How people take it
Safety
Who should avoid
- Taking warfarin — UK regulator and NHS advise avoiding cranberry products
- Active UTI symptoms — see a doctor; cranberry does not treat infection
- Pregnancy — no UTI benefit shown; ask your clinician before using larger amounts
- Fever, back or side pain, blood in urine — may be a kidney infection, needs urgent care
- Large amounts — can cause stomach upset and diarrhoea, especially in young children
Known interactions
Compare with
Head-to-head pages for the pairs people search most.
Questions people ask
Does cranberry juice cure a UTI?
No. A 2023 Cochrane review found no trials showing cranberry treats an existing UTI, and the NHS says there is no evidence it eases symptoms once infection has started. See a doctor for diagnosis and treatment.
Does cranberry prevent recurrent UTIs?
In women with recurrent UTIs, children and people at risk after urinary procedures, the Cochrane review found fewer infections, with a modest effect in women (risk ratio 0.74) and inconsistent trials. It found little or no benefit in older people in care, in pregnancy or with bladder-emptying problems.
Is it safe to take cranberry with warfarin?
The MHRA advises avoiding cranberry products on warfarin and the NHS says the same, based on case reports of raised INR or bleeding. Two small controlled trials found no effect on warfarin levels, so the evidence is mixed; ask your anticoagulant clinic before taking it.
Are capsules better than juice?
Nobody knows. Cochrane rated the evidence comparing juice with tablets as very low certainty. Capsules avoid the sugar in juice, but NCCIH notes processing can lower PAC content.
Sources
- Systematic review Williams G, Stothart CI, Hahn D, Stephens JH, Craig JC, Hodson EM. Cranberries for preventing urinary tract infections. Cochrane Database Syst Rev. 2023.
- Systematic review Jepson RG, Mihaljevic L, Craig JC. Cranberries for treating urinary tract infections. Cochrane Database Syst Rev. 2023.
- Randomised trial Tsiakoulias E, Gravas S, Hadjichristodoulou C, et al. Randomized, placebo-controlled, double-blinded study of prophylactic cranberries use in women with recurrent uncomplicated cystitis. World J Urol. 2024.
- Regulator/health agency NCCIH. Cranberry: Usefulness and Safety. National Center for Complementary and Integrative Health.
- Health service guidance NHS. Cystitis. National Health Service (page last reviewed 11 July 2025).
- Regulator report MHRA. Public Assessment Report: Warfarin: changes to product safety information. December 2009.
- Randomised trial Ansell J, McDonough M, Zhao Y, Harmatz JS, Greenblatt DJ. The absence of an interaction between warfarin and cranberry juice: a randomized, double-blind trial. J Clin Pharmacol. 2009.
- Randomised trial Lilja JJ, Backman JT, Neuvonen PJ. Effects of daily ingestion of cranberry juice on the pharmacokinetics of warfarin, tizanidine, and midazolam. Clin Pharmacol Ther. 2007.
Last reviewed 29 September 2026 · Next review March 2027 · How we rate evidence