Index of Herbs

Evidence review

Goldenseal for UTIs

Hydrastis canadensis

The short answer

Long traditional use

There is no good evidence that goldenseal treats or prevents urinary tract infections: no clinical trial has tested it, and no UTI dose has been established. Its berberine affects E. coli only in laboratory tests and is poorly absorbed. Goldenseal also interferes with many medicines and should not be used in pregnancy or while breastfeeding, so a suspected UTI needs a medical assessment and usually antibiotics.

7 key studies reviewed

Updated October 12, 2026

Key points

  1. 01

    No trials for UTIs

    No clinical trial has tested goldenseal for a bladder or kidney infection, and there is no established UTI dose. NCCIH says no rigorous studies have tested it for any condition.

  2. 02

    Lab effects, not bladder effects

    Berberine blocks E. coli from sticking to cells in the lab, but stopping growth took 1,024 to 2,048 µg/mL, far above the blood levels reached even with pure berberine.

  3. 03

    Berberine studies are not goldenseal

    The only clinical study using berberine for cystitis tested a combination with arbutin, birch, and D-mannose, had no placebo group, and contained no goldenseal.

  4. 04

    Real drug interactions

    In volunteers, goldenseal raised levels of the sedative midazolam by 43% and lowered metformin by 23%. It should be avoided in pregnancy, breastfeeding, and infancy.

  5. 05

    UTIs need prompt care

    Antibiotics treat UTIs. Fever, back or side pain, vomiting, blood in urine, pregnancy, men, children, or no improvement within 48 hours all need medical care.

Goldenseal (Hydrastis canadensis) has not been shown to treat or prevent urinary tract infections (UTIs). No clinical trial has tested goldenseal for a bladder or kidney infection, and there is no evidence-based dose for one. The case for it rests on berberine, a yellow alkaloid in the root that affects E. coli, the bacterium behind most UTIs, in laboratory dishes. The National Center for Complementary and Integrative Health (NCCIH) states that no rigorous studies have evaluated goldenseal for any health condition in people and that very little berberine may be absorbed when goldenseal is swallowed. Goldenseal also changes how the body handles many prescription drugs, and it should not be used in pregnancy, while breastfeeding, or in infants. For a suspected UTI, the useful step is a medical assessment, because antibiotics are the treatment that works.

A UTI happens when bacteria, usually from the bowel, enter the urethra and infect the urinary tract. Bladder infection (cystitis) is the most common type and typically causes burning when passing urine, a frequent or urgent need to go, and sometimes cloudy or bloody urine. A kidney infection is less common but more serious, and the UK’s National Health Service (NHS) warns that it can lead to sepsis if untreated. Goldenseal’s reputation for urinary problems goes back to the nineteenth-century Eclectic physicians, American doctors who favored plant medicines. King’s American Dispensatory (1898) described goldenseal “as a remedy for cystitis” given by mouth and, heavily diluted, used to wash out the bladder, and recommended berberine salt solutions as injections for “catarrh of the bladder.” Today goldenseal is promoted mainly for colds and other upper respiratory infections, often combined with echinacea. LactMed, the NIH database on medicines and breastfeeding, notes its traditional use as an anti-infective, and people often try it for UTIs hoping for a natural alternative to antibiotics.

This page looks at what has actually been studied: the absence of goldenseal trials, the one small clinical study of a berberine-containing combination, the laboratory work on berberine and E. coli, and why poor absorption makes those laboratory results hard to apply to the bladder. It then covers what doses exist (none for UTIs), the herbs with better evidence, especially cranberry for preventing repeat infections, and the safety issues that matter most for someone with a UTI: drug interactions, pregnancy, and the warning signs of a kidney infection. Nothing here is medical advice. Urinary symptoms deserve a proper diagnosis, because the same symptoms can come from other conditions, because the right antibiotic depends on the infection, and because bacteria can reach the kidneys, where infection is more serious.

See also

The full goldenseal monograph Herbs for Urinary Tract Health

02 The trials

Key studies

The trials and reviews that carry the most weight for this question, with the product and dose each one tested. Results apply to the preparation studied.

  1. Genovese et al., 2018

    Preliminary comparison of three supplement combinations, no placebo

    Who
    Adult women with recurrent uncomplicated cystitis (numbers not given in the abstract)
    What and how much
    Berberine, arbutin, and birch extract with D-mannose, with or without forskolin, versus proanthocyanidins with D-mannose; no goldenseal
    How long
    Treatment period plus follow-up (length not given in the abstract)

    Both berberine combinations were followed by fewer cystitis recurrences and lower urine bacterial counts than the proanthocyanidin mix. Funded by PHARMAMOL, a University of Molise spin-off company.

  2. Pannek and Pannek-Rademacher, 2021

    Case series, no control group

    Who
    4 people with tetraplegia and long-term suprapubic catheters
    What and how much
    Homeopathic Hydrastis C30 once weekly, a dilution containing essentially no plant material
    How long
    Long-term, follow-up at least 1 year

    Catheter blockages from encrustation stopped in 3 of 4 people. It did not test herbal goldenseal or treat infection.

  3. Zeng and Zeng, 1999

    Uncontrolled study measuring blood levels

    Who
    Patients with congestive heart failure (56, according to ESCOP)
    What and how much
    Purified berberine, 1.2 g a day by mouth
    How long
    2 weeks

    Even at this dose, which is many times the berberine in a typical goldenseal dose, blood berberine was around 0.1 mg per liter; the authors used 0.11 mg/L as their cut-off.

  4. Chen et al., 2011

    Animal pharmacokinetic study

    Who
    Rats
    What and how much
    Berberine chloride, 100 mg/kg by mouth versus 1 mg/kg intravenously
    How long
    Single doses

    Only 0.68% of swallowed berberine reached the bloodstream, which the authors called a very low absolute bioavailability.

  5. Petronio Petronio et al., 2020

    Laboratory and insect-larva infection study

    Who
    4 uropathogenic E. coli strains, 2 from catheter patients with chronic urinary infections
    What and how much
    Berberine chloride
    How long
    Laboratory assays

    Berberine needed 1,024 to 2,048 µg/mL to inhibit growth. Pretreatment reduced bacterial adhesion to and invasion of bladder cells, and treatment improved larval survival. No external funding.

  6. Sun et al., 1988

    Laboratory study

    Who
    Uropathogenic E. coli
    What and how much
    Berberine sulfate
    How long
    Laboratory assays

    Berberine did not stop bacterial growth but increasingly blocked adhesion to red blood cells and epithelial cells by reducing the fimbriae (hair-like adhesins) the bacteria use to attach.

  7. Corn et al., 2021

    Laboratory disc diffusion test

    Who
    Staphylococcus epidermidis and Escherichia coli
    What and how much
    Goldenseal tincture, alone and in a four-herb formula
    How long
    Laboratory assays

    Goldenseal inhibited the growth of S. epidermidis but not E. coli, the bacterium behind most UTIs.

03 Evidence

What the research shows

Long traditional use

Our rating for Goldenseal for UTIs, based on the studies below.

There are no clinical trials of goldenseal for UTIs. Searches of PubMed and ClinicalTrials.gov for this page in October 2026 found no human trial, completed or registered, of goldenseal or of berberine alone for treating or preventing a urinary infection. NCCIH concludes that there is not enough evidence to say whether goldenseal is useful for any condition, and Memorial Sloan Kettering Cancer Center (MSKCC) states that clinical studies are lacking and that human data are missing even for the minor infections goldenseal is popular for. The European Scientific Cooperative on Phytotherapy (ESCOP), in its 2013 monograph on the root, lists only digestive complaints and gastritis, plus heavy and painful periods as an add-on use, as goldenseal’s traditional indications; UTIs are not among them, and under clinical studies it records “no data available.” The only human report linking Hydrastis to the urinary tract is a case series by Pannek and Pannek-Rademacher (Spinal Cord Series and Cases 2021), in which catheter blockages stopped in three of four people with tetraplegia given homeopathic Hydrastis C30. A 30C dilution contains essentially none of the plant, and the series was about catheter encrustation, not infection, so it says nothing about herbal goldenseal for a UTI.

The closest thing to a clinical study involves berberine, not goldenseal. Genovese and colleagues (Journal of Chemotherapy 2018) gave women with recurrent uncomplicated cystitis one of three supplement combinations, each with D-mannose, a sugar studied for UTI prevention: berberine, arbutin, and birch extract; the same mix plus forskolin; or proanthocyanidins, the compounds credited for cranberry’s effect. The two berberine combinations were followed by fewer recurrences and lower bacterial counts in urine than the proanthocyanidin mix. The study has major limits. The authors called it preliminary, the abstract does not report how many women took part or the size of the differences, there was no placebo or antibiotic comparison, and with three or four active ingredients in each product, any effect cannot be credited to berberine. Its funding is listed as PHARMAMOL, a spin-off company of the University of Molise, where several authors work. None of the products contained goldenseal.

Laboratory studies explain why berberine attracts interest. Sun and colleagues (Antimicrobial Agents and Chemotherapy 1988) found that berberine sulfate, at concentrations that did not stop E. coli growing, increasingly blocked uropathogenic E. coli from attaching to red blood cells and to epithelial (lining) cells by reducing the fimbriae, hair-like structures the bacteria use to grip. This anti-adhesion idea resembles the one proposed for cranberry. Petronio Petronio and colleagues (Molecules 2020), from the University of Molise group, tested berberine chloride on four urinary E. coli strains. Pretreatment reduced the bacteria’s ability to stick to and invade human bladder cells, and berberine improved survival of wax moth larvae infected with the bacteria, but the minimum inhibitory concentration (the lowest concentration that stops growth) was 1,024 to 2,048 µg/mL. Results for whole goldenseal are mixed. In a disc test by Corn and colleagues (Alternative Therapies in Health and Medicine 2021), goldenseal tincture inhibited the skin bacterium Staphylococcus epidermidis but not E. coli.

Absorption is the main reason these laboratory results do not translate. In rats, Chen and colleagues (AAPS PharmSciTech 2011) found that only 0.68% of swallowed berberine reached the bloodstream. In people, Zeng and Zeng (Biomedical Chromatography 1999) gave patients with heart failure 1.2 g of purified berberine a day for two weeks, and blood levels were around 0.1 mg per liter; ESCOP summarizes the peaks as 0.07 to 0.19 mg/L. The growth-inhibiting concentrations in the Petronio study, 1,024 to 2,048 µg/mL, equal roughly 1,000 to 2,000 mg per liter, thousands of times higher. Goldenseal supplies far less berberine than that study used: the capsules in a 2021 interaction study contained 29.8 mg per gram of root. Urine is not blood, and some berberine does leave the body in urine, but ESCOP reports that studies of volunteers’ urine identified mainly metabolites (broken-down forms), most of them conjugated, that is, chemically tagged for excretion. No study has measured whether urine from people taking goldenseal can slow or block bacteria. NCCIH accordingly warns that results from berberine studies may not apply to goldenseal.

Herbs with real UTI evidence are used for prevention or symptom relief, not as substitutes for antibiotics. A 2023 Cochrane review by Williams and colleagues pooled 50 trials with 8,857 participants and found, with moderate certainty, that cranberry products reduced symptomatic, culture-confirmed UTIs in women with recurrent infections (risk ratio 0.74), in children, and after medical procedures, but may offer little or no benefit in pregnancy or for older people in care homes (low certainty). The NHS adds that there is no evidence that cranberry or cystitis sachets treat an infection that has already started. The European Medicines Agency (EMA) accepts bearberry leaf (uva ursi) only as a traditional remedy for symptoms of mild, recurrent lower UTIs in adult women, after a doctor has excluded serious conditions, for no more than a week, and notes that no clinical studies of bearberry alone exist. Goldenseal has neither cranberry’s trials nor bearberry’s regulatory status. Open questions remain, including whether berberine or its breakdown products reach the urine in active form and whether its anti-adhesion effect matters in people, but no trial to answer them is registered on ClinicalTrials.gov.

04 In practice

How it was taken in studies

There is no evidence-based goldenseal dose for a UTI, because no study has tested one. Doses that do exist come from other contexts. ESCOP’s monograph, for digestive complaints, gives 0.5 to 1 g of dried root as a decoction (simmered tea) three times a day, or 0.3 to 1 mL of a 1:1 liquid extract in 60% ethanol three times a day. NCCIH notes that small research studies have given about 3 g a day for short periods without serious harm. In the NIH-funded interaction study by Nguyen and colleagues (Clinical Pharmacology and Therapeutics 2021), volunteers took 1 g three times a day for five days, from capsules containing 29.8 mg of berberine and 25.4 mg of hydrastine per gram, so a full day supplied roughly 90 mg of berberine, a small fraction of the 1.2 g a day of pure berberine that produced only trace blood levels in the Zeng study. These figures describe what people have taken, not what works for an infection, and the interaction study found measurable effects on medicines within days.

Products vary widely. ESCOP sets a minimum of 3.0% berberine and 2.5% hydrastine for goldenseal root of pharmacopoeial quality, and MSKCC notes that the berberine content of goldenseal products can vary widely. Berberine supplements are a different product from goldenseal root, and NCCIH cautions that berberine results may not apply to goldenseal. A goldenseal tea is bitter and has never been tested for urinary symptoms. The bladder washes described in King’s American Dispensatory belong to nineteenth-century medicine and are not something to attempt at home. Goldenseal also does not hide drugs on a urine test: a US Forest Service review traces that idea to John Uri Lloyd’s 1900 novel Stringtown on the Pike and notes that research has disproved it, and MSKCC notes that it may simply darken the urine sample. Wild goldenseal is under pressure from harvesting. It has been listed on Appendix II of the Convention on International Trade in Endangered Species (CITES) since 1997, and United Plant Savers keeps it on its At-Risk list and recommends cultivated sources.

Because there is no evidence that goldenseal works for a UTI, there is no point at which to expect an effect, and waiting to see whether it helps carries real risk. The NHS advises seeking an urgent appointment if UTI symptoms do not improve within 48 hours of starting treatment or treating it yourself, and sooner for anyone in a higher-risk group. For people who keep getting UTIs, the better-studied options are cranberry products and D-mannose, for which the NHS says there is some evidence, along with prevention steps and medical treatments a doctor can discuss. Neither replaces antibiotics for an infection that has already started.

05 Caution

Before you try goldenseal

NCCIH reports that small studies giving about 3 g of goldenseal a day for short periods found no serious harmful effects, but that the safety of longer use is uncertain. MSKCC advises against long-term use because of toxicity in animal studies, in which high doses of goldenseal root powder over two years caused liver tumors in rodents. MSKCC also records two case reports: dangerously high blood sodium in a pre-teen with diabetic ketoacidosis who had taken goldenseal for two weeks, and a sun-sensitivity reaction in a woman using a multi-ingredient supplement. ESCOP mentions exaggerated reflexes, depression, delirium, vomiting, and cyanosis (a blue tinge from low oxygen) after overdose, though without case reports. Some commercial goldenseal products contain other herbs not listed on the label, according to NCCIH, which adds uncertainty about what is being taken.

Goldenseal should not be used in pregnancy, while breastfeeding, or in infants, according to NCCIH, ESCOP, and MSKCC. The concern is berberine’s effect on bilirubin, the yellow pigment that causes jaundice: LactMed explains that berberine can push bilirubin off albumin, its carrier protein in the blood, and that free bilirubin can build up in a newborn’s brain and cause damage (kernicterus). No data exist on whether goldenseal passes into breast milk. This matters for UTIs because urinary symptoms in pregnancy always need prompt medical assessment, and cranberry has not been shown to prevent UTIs in pregnancy either. NCCIH says goldenseal should not be given to infants, and a child with urinary symptoms needs assessment rather than herbs: the NHS advises an urgent appointment for any child aged 15 or under with a possible UTI, and the US Centers for Disease Control and Prevention (CDC) says to contact a professional right away for a baby under 3 months with a temperature of 100.4 °F (38 °C) or higher.

Goldenseal’s drug interactions are well documented in human studies. In healthy volunteers it inhibits CYP3A4 and CYP2D6, two enzymes that clear many prescription drugs, and MSKCC advises not taking it with drugs cleared by those enzymes, with the diabetes drug metformin, or with the leukemia drug bosutinib. In the study by Nguyen and colleagues (2021), funded by NCCIH and the NIH Office of Dietary Supplements through the Center of Excellence for Natural Product Drug Interaction Research, goldenseal raised exposure to the sedative midazolam by 43% and lowered metformin exposure by 23% in 16 healthy adults; NCCIH says that drop could hinder blood sugar control. This is relevant because the NHS lists diabetes among the reasons to seek urgent care for a UTI. No study has tested goldenseal alongside the antibiotics used for UTIs, so anyone prescribed an antibiotic should tell their prescriber or pharmacist before adding goldenseal, or any combination product that contains it.

Get medical care promptly rather than trying goldenseal or any herb if you have a fever, chills, or shivering; pain in your back or side just under the ribs; nausea or vomiting; or blood in your urine, which may look pink, red, or dark brown. The CDC lists fever, chills, back or side pain, and nausea or vomiting as signs of a kidney infection. The NHS also advises urgent assessment for anyone who is pregnant, male, aged 65 or over, a child, diabetic, catheterized, or immunosuppressed, for anyone with repeated UTIs, and for symptoms that worsen quickly or do not improve within 48 hours. Confusion, drowsiness, or difficulty speaking needs emergency care. Some of these signs can mean a kidney infection, which the NHS warns can be serious if it is not treated because it could cause sepsis. The CDC also notes that UTI symptoms can resemble those of sexually transmitted infections, another reason a diagnosis matters.

06 Questions

Frequently Asked Questions

There is no good evidence that it does. No clinical trial has tested goldenseal for a bladder or kidney infection, and NCCIH says no rigorous studies have tested it for any condition. Its berberine affects E. coli in the laboratory, but very little is absorbed when goldenseal is swallowed. Antibiotics are the treatment that works for a UTI. See a doctor promptly, and urgently if you have a fever, back or side pain, vomiting, blood in your urine, are pregnant, or are a man or a child.

There is none, because no study has tested goldenseal for a UTI. The doses that exist come from other uses: ESCOP gives 0.5 to 1 g of dried root as a tea three times a day for digestive complaints, and NCCIH notes that about 3 g a day has been used for short periods without serious harm. Those amounts change how the body handles medicines within days. Taking more goldenseal will not make up for the lack of evidence, and a UTI that has not improved within 48 hours needs medical care.

Not in any way that has been shown. Berberine is one of several alkaloids in goldenseal and is also sold on its own as a supplement. In the lab it stops E. coli from sticking to cells, but stopping growth took concentrations thousands of times higher than the blood levels reached with 1.2 g of pure berberine a day. The only clinical study combined berberine with arbutin, birch, and D-mannose, had no placebo group, and cannot show what berberine did. Berberine also interacts with medicines.

That combination has never been studied, so there is no evidence it helps and no safety data. Goldenseal inhibits CYP3A4 and CYP2D6, enzymes that clear many prescription drugs, and it lowered levels of the diabetes drug metformin by 23% in one study. If a clinician has prescribed an antibiotic, take the full course as directed and ask your pharmacist before adding goldenseal or any cold or immune product that lists it as an ingredient. Tell them about every other medicine you take, too.

No. NCCIH, ESCOP, and MSKCC all advise against goldenseal in pregnancy and while breastfeeding, and it should never be given to babies. Its berberine can push bilirubin off its carrier protein in the blood, which raises the risk of brain damage from jaundice in newborns. Any possible UTI in pregnancy needs prompt medical care, and a clinician can choose a treatment suitable for pregnancy. Cranberry has not been shown to prevent UTIs in pregnancy either.

Cranberry has the strongest evidence, but for prevention only: a 2023 Cochrane review of 50 trials found it reduced repeat UTIs in women with recurrent infections, in children, and after medical procedures. Uva ursi (bearberry leaf) is accepted in Europe as a traditional remedy for symptoms of mild recurrent bladder infections in adult women, for up to a week, after a doctor has ruled out anything serious. Neither treats an active infection. Our urinary health guide compares the options.

07 References

Sources

These references support the claims on this page. They are not an endorsement of any product. The goldenseal monograph carries its own full source list.

  1. Goldenseal

    National Center for Complementary and Integrative Health (NIH), 2025

    Updated February 2025: not enough evidence for any condition; no rigorous human studies; little berberine absorbed orally, so berberine results may not apply; about 3 g a day short term without serious harm; metformin about 25% lower; avoid in pregnancy, breastfeeding, and infants.

  2. Hydrastis rhizoma (Goldenseal rhizome)

    ESCOP Monographs, European Scientific Cooperative on Phytotherapy, 2013

    Indications limited to digestive complaints, gastritis, and adjuvant use in heavy or painful periods; no clinical data; decoction and liquid extract doses; not in pregnancy or lactation; CYP3A4 and CYP2D6 interactions; human berberine plasma peaks of 0.07–0.19 mg/L; urinary metabolites.

  3. Goldenseal

    Memorial Sloan Kettering Cancer Center, About Herbs, 2022

    Human data lacking for infections; avoid long-term use; do not combine with CYP3A4 or CYP2D6 substrates, metformin, or bosutinib; avoid in pregnancy and nursing; berberine content varies; case reports; may darken urine in drug testing.

  4. Goldenseal

    Drugs and Lactation Database (LactMed), National Institute of Child Health and Human Development (PubMed 30000926), 2025

    Revised May 2025: high-quality efficacy studies lacking; no data on passage into breast milk; berberine displaces bilirubin from albumin, risking infant brain damage; most sources advise avoiding neonatal exposure; ineffective at masking drugs in urine.

  5. Effects of a new combination of plant extracts plus d-mannose for the management of uncomplicated recurrent urinary tract infections

    Journal of Chemotherapy (PubMed 29078739), 2018

    Genovese et al.: preliminary study of berberine, arbutin, and birch (with or without forskolin) versus proanthocyanidins, all with D-mannose; fewer recurrences with berberine mixes; funding listed in Europe PMC as PHARMAMOL, a University of Molise spin-off.

  6. In Vitro and In Vivo Biological Activity of Berberine Chloride against Uropathogenic E. coli Strains Using Galleria mellonella as a Host Model

    Molecules (PubMed 33137930), 2020

    Petronio Petronio et al.: berberine MICs of 1,024–2,048 µg/mL against four urinary E. coli strains; reduced adhesion to and invasion of bladder cells; improved larval survival; no external funding.

  7. Assessing Transporter-Mediated Natural Product-Drug Interactions Via In vitro-In Vivo Extrapolation: Clinical Evaluation With a Probe Cocktail

    Clinical Pharmacology and Therapeutics (PubMed 33174626), 2021

    Nguyen et al.: 16 healthy volunteers, goldenseal 1 g three times daily (29.8 mg berberine per gram); midazolam AUC ratio 1.43, metformin AUC ratio 0.77; funded by NCCIH and the NIH Office of Dietary Supplements via the NaPDI Center.

  8. Urinary tract infections (UTIs)

    National Health Service (NHS), UK, 2025

    Symptoms; urgent-care triggers including pregnancy, men, children 15 or under, diabetes, fever, back pain, blood in urine, and no improvement within 48 hours; kidney infection can cause sepsis; cranberry and D-mannose may help prevent but not treat UTIs.

  9. Urinary Tract Infection Basics

    US Centers for Disease Control and Prevention, 2026

    Antibiotics treat UTIs; kidney infection signs are fever, chills, back or side pain, and nausea or vomiting; urgent care for infants under 3 months with fever of 100.4 °F; UTI symptoms can resemble STIs.

  10. Cranberries for preventing urinary tract infections

    Cochrane Database of Systematic Reviews (PubMed 37068952), 2023

    Williams et al.: 50 trials, 8,857 participants; cranberry reduced symptomatic UTIs in women with recurrent UTIs (RR 0.74), children, and after interventions; little or no benefit in pregnancy or institutionalized older people.

  11. Uvae ursi folium (Bearberry leaf): summary for the public

    European Medicines Agency (EMA/181295/2018), 2018

    Traditional use only for symptoms of mild recurrent lower UTIs in adult women after a doctor has excluded serious conditions; maximum one week; no clinical studies of bearberry alone.

  12. Hydrastis (U. S. P.)—Hydrastis. (King’s American Dispensatory)

    Felter and Lloyd, King’s American Dispensatory, via Henriette’s Herbal Homepage, 1898

    Eclectic use of goldenseal for cystitis, given internally and diluted as a bladder wash; berberine sulfate solutions as injections for catarrh of the bladder.

  13. Goldenseal (Hydrastis canadensis): an annotated bibliography

    US Forest Service, Southern Research Station (Gen. Tech. Rep. SRS-88), 2005

    Predny and Chamberlain: drug-test masking myth traced to Lloyd’s 1900 novel and disproved by research; CITES Appendix II listing since 1997.

  14. Species At-Risk List

    United Plant Savers, 2026

    Goldenseal listed as At-Risk; At-Risk plants should be used in cultivated forms whenever possible, with very limited, monitored wild harvest.

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