Home Ingredients Uva ursi (Bearberry)

Uva ursi (Bearberry)

Arctostaphylos uva-ursi
Evidence Level
Preliminary
3 Clinical Trials
5 Documented Benefits
1/5 Evidence Score

Uva ursi (bearberry) is an evergreen shrub whose dried leaf is a traditional European herbal preparation for the lower urinary tract. Its marker compound, arbutin, is absorbed and excreted in urine mostly as hydroquinone conjugates, and laboratory tests link those metabolites to antibacterial activity. The European Medicines Agency accepts bearberry leaf only as a traditional herbal medicine for adult women, based on long-standing use rather than clinical proof, and limits a course to one week. Two modern randomized trials in women with suspected urinary tract infection did not show symptom relief: one found no difference from placebo, and the other found a higher symptom burden than a single antibiotic dose. Hydroquinone exposure is the main safety concern, so it is not recommended in pregnancy, breastfeeding, under age 18, or in men, and it is contraindicated with kidney disorders.

Studied Dose Trials used 630 mg arbutin a day for 5 days and 3,600 mg a day of a 20% arbutin extract (stated to provide 686 mg arbutin) for 3 to 5 days; neither relieved symptoms better than its comparator. The EMA monograph allows 200 to 840 mg arbutin a day for no more than one week.
Active Compound Arbutin (hydroquinone-O-β-D-glucoside, about 5% to 16% of the leaf) and methylarbutin (up to 4%), with tannins at about 10% to 20%. Arbutin is excreted mainly as hydroquinone glucuronide and hydroquinone sulfate, with little free hydroquinone.

Benefits

Traditional European herbal use for the lower urinary tract

The European Medicines Agency accepts bearberry leaf only as a traditional herbal medicine, a status based on at least 30 years of use rather than clinical proof. Its wording covers relief of burning or frequent urination in women with mild recurrent lower urinary tract infections, after a doctor has excluded serious conditions, for no more than one week. The agency found no clinical efficacy data suitable for a stronger listing.

Supported by Trial 1, Trial 3

Urinary symptom scores in a placebo-controlled trial in women

In a UK primary care trial, 382 women aged 18 to 70 with suspected lower urinary tract infection took uva ursi extract or placebo, all with a backup antibiotic prescription. Frequency symptom scores on days 2 to 4 did not differ from placebo, and antibiotic use (39.9% versus 47.4%) was not significantly lower. No safety concerns were recorded.

Supported by Trial 1, Trial 2

Antibiotic use, symptom burden and safety in a randomized trial in women

In a double-blind trial at 42 German family practices, 398 women with suspected uncomplicated urinary tract infection took uva ursi (630 mg arbutin a day for 5 days) or a single antibiotic dose. Only the uva ursi group deferred antibiotics, so it used 63.6% fewer courses over 28 days by design, but it had a higher symptom burden, failing the noninferiority test, and 8 versus 2 women developed a kidney infection.

Supported by Trial 2, Trial 1

Arbutin metabolites reach the urine after oral intake

In 16 healthy volunteers, 64.8% to 66.7% of a single oral arbutin dose from bearberry leaf extract was excreted in urine as hydroquinone and its glucuronide and sulfate conjugates, with tablets and a liquid performing similarly. In a three-person study, free hydroquinone was negligible in two people and 5.6% of the dose in the third. These studies measure exposure, not symptom relief.

Supported by Trial 3

Antibacterial activity of leaf extracts in laboratory tests

Various bearberry leaf extracts inhibited E. coli, Proteus, Klebsiella, Staphylococcus aureus and Candida albicans in laboratory tests, although one ethanol extract showed no activity against 25 bacteria. Urine collected after oral arbutin inhibited bacteria only after it was made alkaline. Two randomized trials in women did not show this as symptom relief.

Supported by Trial 3, Trial 1

Mechanism of action

1

Arbutin conversion to hydroquinone conjugates in urine

Oral arbutin is absorbed and conjugated, and most of it is excreted in urine as hydroquinone glucuronide and hydroquinone sulfate. Older laboratory tests found that urine collected after arbutin inhibited bacteria only when made alkaline (pH 8), while a four-volunteer study suggested E. coli can take up the conjugates and release free hydroquinone without alkalinization. Which compound acts is still unresolved.

2

Effects on bacterial cell surfaces in laboratory tests

A bearberry leaf decoction increased the cell surface hydrophobicity and aggregation of E. coli strains in laboratory tests, and a similar effect on Helicobacter pylori was matched by tannic acid tested alongside, which points to tannins as a contributor. These effects have not been measured in people.

3

Tannin content and anti-inflammatory findings in animals

Bearberry leaf contains about 10% to 20% tannins, which herbal references cited by the EMA link to the nausea and stomach upset some users report. An oral leaf extract reduced swelling in a mouse contact dermatitis model at 100 mg/kg or more. No human study has tested an anti-inflammatory effect in the urinary tract.

Clinical trials

1
ATAFUTI: uva ursi extract versus placebo in women in UK primary care
PubMed

2 x 2 factorial, placebo-controlled randomized trial (ISRCTN43397016); the uva ursi versus placebo comparison was blinded. Dose and funding from the published protocol: 3,600 mg/day of a 20% arbutin extract for 3 to 5 days, funded by the NIHR School for Primary Care Research. (Moore et al. 2019, Clin Microbiol Infect)

382 women aged 18 to 70 in UK primary care with dysuria, urgency or frequency and suspected lower urinary tract infection, randomized to uva ursi extract or placebo, with or without advice to take ibuprofen. All received a delayed (backup) antibiotic prescription.

Frequency symptom scores on days 2 to 4 did not differ between uva ursi and placebo (-0.06; 95% CI -0.33 to 0.21; p 0.661). Antibiotic use was 39.9% with uva ursi versus 47.4% with placebo (OR 0.59; 95% CI 0.22 to 1.58; p 0.293), not a significant reduction. Advice to take ibuprofen did lower antibiotic use (34.9% versus 51.0%). No safety concerns and no upper tract infections were recorded.

2
REGATTA: uva ursi versus a single antibiotic dose in German family practice
PubMed

Double-blind, double-dummy randomized controlled trial at 42 German family practices (NCT03151603). Per the protocol, tablets were Arctuvan (105 mg arbutin each), the trial was funded by the German Federal Ministry of Education and Research, and the tablet maker was contracted only to produce and repack the medication. (Gágyor et al. 2021, Clin Microbiol Infect)

398 adult women with suspected uncomplicated urinary tract infection: uva ursi 2 tablets three times daily for 5 days (630 mg arbutin a day; n=207) or a single 3 g dose of fosfomycin (n=191), each group taking the other's placebo. The uva ursi group received antibiotics only for persistent or worsening symptoms.

The two primary outcomes split. Antibiotic courses on days 0 to 28 were 63.6% lower with uva ursi (95% CI 53.6 to 71.4; p < 0.0001). Total symptom burden on days 0 to 7 was 136.5% of the fosfomycin group (95% CI 122.7 to 151.9), failing the 125% noninferiority margin. Pyelonephritis occurred in 8 women on uva ursi versus 2 on fosfomycin (mean difference 2.8; 95% CI 0.2 to 5.9; p 0.067). Other adverse events were similar. The authors concluded that uva ursi reduced antibiotic use but led to a higher symptom burden and more safety concerns than fosfomycin.

3
Urinary excretion of arbutin metabolites in healthy volunteers
PubMed

Randomized two-way crossover pharmacokinetic study of a single oral dose of bearberry leaf dry extract. (Schindler et al. 2002, J Clin Pharmacol)

16 healthy volunteers given bearberry leaf dry extract as film-coated tablets or as an aqueous solution.

64.8% (tablets) and 66.7% (solution) of the arbutin dose was excreted in urine as hydroquinone equivalents (p 0.61), with a relative bioavailability of 103.3% for the tablets and substantial variation between people. Metabolite patterns (hydroquinone, its glucuronide and its sulfate) did not differ between forms. No symptom outcome was measured.

Side effects and drug interactions

Common Potential side effects

Nausea, vomiting and stomach ache are reported; herbal references cited by the EMA attribute these largely to the leaf's high tannin content.
Hydroquinone is the main safety concern. In a two-year rodent study, oral hydroquinone gave some evidence of cancer, and adequate genotoxicity tests on bearberry leaf are lacking. The EMA judges the risk minimal for short courses at the recommended dose, but prolonged use is discouraged and has been linked to liver impairment in herbal references.
Greenish-brown discoloration of the urine can occur.
One case report described bilateral bull's-eye maculopathy (retinal damage) in a 56-year-old woman who had taken uva ursi for 3 years.
Other reported effects include irritability, insomnia and a faster heart rate. Herbal references describe overdose as irritating the bladder and urinary tract, with painful urination and blood in the urine; the EMA notes these overdose descriptions are not supported by case reports, and its monograph lists no reported overdose.
Not recommended in pregnancy or breastfeeding, under age 18, or in men; contraindicated with kidney disorders (EMA monograph).
In a randomized trial in women with suspected urinary tract infection, 8 of 207 women given uva ursi in place of an initial antibiotic developed a kidney infection, versus 2 of 191 given a single fosfomycin dose (p 0.067, not statistically significant; the authors still judged it a safety concern). The EMA monograph advises seeing a doctor if symptoms last more than 4 days or worsen, or if fever, spasms or blood in the urine appear.

Important Drug interactions

The EMA monograph lists no documented drug interactions for bearberry leaf.
Products that make urine acidic: German Commission E advice, as summarized by the EMA, is not to combine them with bearberry, since acidic urine may reduce its antibacterial action.
Urinary alkalinizers (sodium bicarbonate): traditionally paired with bearberry, but the EMA assessment notes usual doses alkalinize urine only briefly and that a benefit in people is doubtful.
Diuretics: a herbal reference cited by the EMA suggests a sodium-sparing effect could offset thiazide and loop diuretics; no case report supports it.
Drugs cleared by CYP3A enzymes: water and methanol extracts inhibited CYP3A4, 3A5 and 3A7 in a laboratory test; no human interaction has been reported.

Frequently asked questions about Uva ursi (Bearberry)

What is Uva ursi used for?

Uva ursi (bearberry leaf) is a traditional European herbal preparation for the lower urinary tract. The European Medicines Agency accepts it only as a traditional-use product for short-term relief of burning or frequent urination in adult women, after a doctor has excluded serious conditions. NutraSmarts does not list it under a health category because two modern randomized trials did not show symptom relief.

What did randomized trials of uva ursi find?

In a UK trial of 382 women with suspected urinary tract infection, uva ursi extract did not reduce frequency symptoms or antibiotic use significantly compared with placebo. In a German trial of 398 women, women given uva ursi used 63.6% fewer antibiotic courses than women given a single fosfomycin dose, because by design only the uva ursi group deferred antibiotics, but they had a higher symptom burden, and 8 versus 2 women developed pyelonephritis. It is not a substitute for medical care.

What is the recommended dosage of Uva ursi?

The EMA monograph allows dry extracts giving 200 to 840 mg arbutin derivatives a day in 2 to 4 doses, or a tea of 1.5 to 4 g leaf in 150 ml water 2 to 4 times daily (maximum 8 g), for adult women only and for no more than one week. A doctor should be consulted if symptoms last more than 4 days. Older German guidance adds no more than five courses a year without medical advice.

Is Uva ursi safe, and does it have side effects?

Nausea, vomiting, stomach ache and greenish-brown urine are reported. Its hydroquinone content is the main concern, so the EMA limits use to one week and does not recommend it in pregnancy, breastfeeding, under age 18 or in men, and it is contraindicated with kidney disorders. One case of retinal damage was reported after 3 years of use. In one trial, 8 of 207 women taking uva ursi instead of an initial antibiotic developed a kidney infection, versus 2 of 191 given an antibiotic. See a doctor if symptoms last more than 4 days, worsen, or come with fever or blood in the urine.

What is Uva ursi?

Uva ursi (bearberry) is an evergreen shrub whose dried leaf is a traditional European herbal preparation for the lower urinary tract. Its marker compound, arbutin, is absorbed and excreted in urine mostly as hydroquinone conjugates, and laboratory tests link those metabolites to antibacterial activity.

Does Uva ursi interact with any medications?

Possible interactions include: The EMA monograph lists no documented drug interactions for bearberry leaf. Products that make urine acidic: German Commission E advice, as summarized by the EMA, is not to combine them with bearberry, since acidic urine may reduce its antibacterial action. If you take prescription medication, check with a pharmacist or doctor before using it.

How strong is the scientific evidence for Uva ursi?

NutraSmarts rates the evidence for Uva ursi as Preliminary (1 out of 5). It is backed by 3 study summaries and 11 cited references summarized on this page. A higher rating reflects more, larger, and better-designed human studies.

References(11 citations)

Evidence ratings on NutraSmarts are based on the totality of human clinical research, with emphasis on randomized controlled trials, meta-analyses, and systematic reviews. The references below directly support claims made throughout this page.

  1. Moore M, Trill J, Simpson C, Webley F, Radford M, Stanton L, Maishman T, Galanopoulou A, Flower A, Eyles C, Willcox M, Hay AD, van der Werf E, Gibbons S, Lewith G, Little P, Griffiths G. Uva-ursi extract and ibuprofen as alternative treatments for uncomplicated urinary tract infection in women (ATAFUTI): a factorial randomized trial. Clin Microbiol Infect. 2019;25(8):973-980. doi: 10.1016/j.cmi.2019.01.011.PubMedUsed to support: Factorial randomized trial in 382 women aged 18 to 70 with suspected lower urinary tract infection in UK primary care. Frequency symptom scores on days 2 to 4 did not differ between uva ursi extract and placebo (-0.06; p 0.661), and antibiotic use was 39.9% versus 47.4% (OR 0.59; p 0.293), not significantly lower. Ibuprofen advice reduced antibiotic use. No safety concerns or upper tract infections were recorded.
  2. Schindler G, Patzak U, Brinkhaus B, von Niecieck A, Wittig J, Krähmer N, Glöckl I, Veit M. Urinary excretion and metabolism of arbutin after oral administration of Arctostaphylos uvae ursi extract as film-coated tablets and aqueous solution in healthy humans. J Clin Pharmacol. 2002;42(8):920-7. doi: 10.1177/009127002401102740.PubMedUsed to support: Randomized crossover pharmacokinetic study in 16 healthy volunteers given a single oral dose of bearberry leaf dry extract as film-coated tablets or aqueous solution. 64.8% and 66.7% of the arbutin dose was excreted in urine as hydroquinone equivalents (hydroquinone, hydroquinone glucuronide and hydroquinone sulfate), with similar results for both forms. It shows that arbutin metabolites reach the urine; it did not test antibacterial activity or symptom relief.
  3. Gágyor I, Hummers E, Schmiemann G, Friede T, Pfeiffer S, Afshar K, Bleidorn J. Herbal treatment with uva ursi extract versus fosfomycin in women with uncomplicated urinary tract infection in primary care: a randomized controlled trial. Clin Microbiol Infect. 2021;27(10):1441-1447. doi: 10.1016/j.cmi.2021.05.032.PubMedUsed to support: The REGATTA trial: a double-blind randomized controlled trial in 42 German family practices. 398 women with suspected uncomplicated urinary tract infection were assigned to uva ursi extract 105 mg, 3 x 2 tablets daily for 5 days (n=207), or a single 3 g dose of fosfomycin (n=191), each group also taking the other's placebo. Antibiotic courses over days 0 to 28 were 63.6% lower with uva ursi (95% CI 53.6 to 71.4; p < 0.0001), but the co-primary non-inferiority outcome failed: total symptom burden over days 0 to 7 was 136.5% of the fosfomycin group (95% CI 122.7 to 151.9) against a prespecified 125% margin. Eight women on uva ursi developed pyelonephritis versus two on fosfomycin (mean difference 2.8; 95% CI 0.2 to 5.9; p 0.067). The authors concluded that uva ursi reduced antibiotic use but led to a higher symptom burden and more safety concerns than fosfomycin.
  4. Trill J, Simpson C, Webley F, Radford M, Stanton L, Maishman T, Galanopoulou A, Flower A, Eyles C, Willcox M, Hay A, Griffiths G, Little P, Lewith G, Moore M. Uva-ursi extract and ibuprofen as alternative treatments of adult female urinary tract infection (ATAFUTI): study protocol for a randomised controlled trial. Trials. 2017;18(1):421. doi: 10.1186/s13063-017-2145-7.PubMedUsed to support: Published protocol of the ATAFUTI trial (same trial as Moore 2019, not a separate study). The uva ursi product was an extract containing 20% arbutin, given as 3,600 mg a day (stated to provide 686 mg arbutin) for 3 to 5 days, with a sugar beet fiber placebo. Funded by the NIHR School for Primary Care Research; the authors declared no competing interests.
  5. Afshar K, Fleischmann N, Schmiemann G, Bleidorn J, Hummers-Pradier E, Friede T, Wegscheider K, Moore M, Gágyor I. Reducing antibiotic use for uncomplicated urinary tract infection in general practice by treatment with uva-ursi (REGATTA) - a double-blind, randomized, controlled comparative effectiveness trial. BMC Complement Altern Med. 2018;18(1):203. doi: 10.1186/s12906-018-2266-x.PubMedUsed to support: Published protocol of the REGATTA trial (same trial as Gágyor 2021, not a separate study). The product was an aqueous bearberry leaf dry extract (Arctuvan, 105 mg arbutin per tablet), 2 tablets three times daily, for 630 mg arbutin a day. Funded by the German Federal Ministry of Education and Research; the tablet maker was contracted only to produce and repack the trial medication.
  6. Quintus J, Kovar KA, Link P, Hamacher H. Urinary excretion of arbutin metabolites after oral administration of bearberry leaf extracts. Planta Med. 2005;71(2):147-52. doi: 10.1055/s-2005-837782.PubMedUsed to support: Assay development paper with a preliminary pharmacokinetic study in 3 volunteers given an aqueous bearberry leaf extract. More than half of the arbutin dose was excreted within 4 hours, mainly as hydroquinone glucuronide and sulfate, and more than 75% within 24 hours. Free hydroquinone was negligible in 2 of 3 people and 5.6% of the dose in the third.
  7. Siegers C, Bodinet C, Ali SS, Siegers CP. Bacterial deconjugation of arbutin by Escherichia coli. Phytomedicine. 2003;10 Suppl 4:58-60. doi: 10.1078/1433-187x-00301.PubMedUsed to support: Four volunteers took a commercial arbutin product (6 dragees of Cystinol akut, 420 mg arbutin), and their urine was incubated with an E. coli suspension or an enzyme. E. coli released 2.3 times more free hydroquinone than the enzyme, and hydroquinone was concentrated about 20-fold inside the bacteria. The authors suggest urine alkalinization may not be needed for hydroquinone release. A small laboratory study of urine, not a clinical outcome.
  8. de Arriba SG, Naser B, Nolte KU. Risk assessment of free hydroquinone derived from Arctostaphylos Uva-ursi folium herbal preparations. Int J Toxicol. 2013;32(6):442-53. doi: 10.1177/1091581813507721.PubMedUsed to support: Review estimating that a daily dose of bearberry leaf extract with 420 mg arbutin derivatives releases free hydroquinone in urine at up to 11 µg/kg body weight a day, against an estimated permitted daily exposure of 100 µg/kg. It reports no direct human evidence that free hydroquinone causes liver, kidney or tumor effects. The first author is affiliated with a German company, Schaper & Brümmer GmbH & Co KG, and its safety conclusion is limited to the recommended use conditions.
  9. Wang L, Del Priore LV. Bull's-eye maculopathy secondary to herbal toxicity from uva ursi. Am J Ophthalmol. 2004;137(6):1135-7. doi: 10.1016/j.ajo.2004.01.004.PubMedUsed to support: Case report of a 56-year-old woman who took uva ursi for 3 years and developed bilateral bull's-eye maculopathy with reduced visual acuity. The authors suggest uva ursi, a melanin synthesis inhibitor, as the cause. A single case; it cannot establish how often this happens.
  10. European Medicines Agency, Committee on Herbal Medicinal Products (HMPC). European Union herbal monograph on Arctostaphylos uva-ursi (L.) Spreng., folium. Final (EMA/HMPC/750269/2016). European Medicines Agency. 2018;Adopted 30 January 2018. Not PubMed-indexed..SourceUsed to support: Not PubMed-indexed (EMA regulatory monograph, read in full). Traditional-use indication only: relief of burning or frequent urination in women with mild recurrent lower urinary tract infections after serious conditions are excluded by a doctor. Dry extracts 200 to 840 mg arbutin derivatives a day; tea 1.5 to 4 g in 150 ml water 2 to 4 times daily (maximum 8 g); not more than one week; see a doctor if symptoms last over 4 days. Not recommended under 18, in men, or in pregnancy and lactation; contraindicated in kidney disorders. Nausea, vomiting and stomach ache reported; greenish-brown urine possible; no interactions reported; adequate genotoxicity tests not performed.
  11. European Medicines Agency, Committee on Herbal Medicinal Products (HMPC). Assessment report on Arctostaphylos uva-ursi (L.) Spreng., folium. Final (EMA/HMPC/750266/2016). European Medicines Agency. 2018;Adopted 30 January 2018. Not PubMed-indexed..SourceUsed to support: Not PubMed-indexed (EMA assessment report, read in full). Finds no clinical efficacy data for bearberry leaf alone and accepts only traditional use. Summarizes in vitro antibacterial and cell-surface data, urine activity only at pH 8, the doubtful effect of urinary alkalinization, constituents (arbutin 5 to 16%, tannins 10 to 20%), a mouse anti-inflammatory study, hydroquinone rodent carcinogenicity, in vitro CYP3A inhibition, a possible diuretic interaction not supported by case reports, Commission E advice of no more than one week and five courses a year, and adverse effects including nausea, vomiting, irritability, insomnia and faster heart rate.