Herbs & Botanicals · Traditional urinary herb
Gravel root
Eutrochium purpureum · also called Joe-Pye weed, kidney root, sweet Joe-Pye weed
Gravel root is the root of Joe-Pye weed, an old North American folk remedy for urinary stones and bladder trouble. We found no human study of it for any use. Its plant group can contain liver-toxic pyrrolizidine alkaloids, and gravel root itself has not been tested for them. Avoid it in pregnancy, and see a doctor for kidney stones or urinary pain.
General information, not medical advice. Last substantive update · Not medically reviewed. A named clinician has not signed off on this page. How this page is made
About Gravel root
Gravel root is the root of Eutrochium purpureum (Joe-Pye weed), long used in North American folk medicine for urinary stones and urinary infections. We found no human study of any use. Its plant group contains liver-toxic pyrrolizidine alkaloids, but gravel root itself has not been analysed in the sources we read.
What it is
Gravel root is the root of a tall North American wildflower in the daisy family. The accepted botanical name is Eutrochium purpureum; older labels say Eupatorium purpureum. 'Gravel' is an old word for small urinary stones.
It is not the same as boneset, a related herb with its own page.
What makes it distinctive
It is one of a group of herbs traditionally taken for the urinary tract, including hydrangea root on this site. Unlike some of them, it has a safety question hanging over it: relatives in the same genus contain pyrrolizidine alkaloids.
What people use it for
Traditional uses include urinary stones, bladder and prostate infections, painful urination, rheumatism, gout and fever. A consumer drug reference rates the evidence for every one of these 'insufficient'.
We searched PubMed and found no human or animal study of any of these uses.
What the research shows
Almost nothing. The few papers are lab work: a cell-culture screen, an oil study on leaves and stems, and chemistry on relatives. Evidence is extremely sparse and we have not padded it.
The most useful research is about boneset, which was shown to contain pyrrolizidine alkaloids in all 49 samples tested, with high levels in teas and tinctures.
At a glance
Traditional uses history, not proof
- Folk remedy for urinary and kidney stones, bladder and prostate infections
- Traditional use for rheumatism, gout and fevers
- Called 'kidney root' for its traditional diuretic use
Studied for research
- Urinary and kidney stones: no human study
- Bladder and prostate infections: no human study
- Joint pain, gout, fever: no study
- Cancer cells and fungi: lab only
Main compounds
- Pyrrolizidine alkaloids (present in relatives; not measured in gravel root)
- Volatile oil (leaves and stems; lab only)
Common forms
- Dried root
- Tea (decoction)
- Tincture
- Capsule or powder
Research links: Boneset page on this site · Hydrangea root page on this site · RxList gravel root page · Boneset alkaloid study (PubMed) · Research Library · Genes & Biomarkers Library
The plant and its history
- Accepted scientific name
- Eutrochium purpureum (L.) E.E.Lamont
- Naming authority
- (L.) E.E.Lamont
- Synonyms
- Eupatorium purpureum L. / Michx.; Eupatoriadelphus purpureus
- Common names
- Gravel root (English); Joe-Pye weed (English); Sweet Joe-Pye weed (English); Kidney root (English); Queen of the meadow (English); Purple boneset (English)
- Botanical family
- Asteraceae (the daisy family, which includes ragweed).
- Classification
- Plantae > Tracheophyta > Magnoliopsida > Asterales > Asteraceae > Eutrochium > Eutrochium purpureum
- Native range
- Not verified from a primary source we read (a North American plant per the traditional-use sources).
- Habitat
- Not verified.
- What the plant looks like
- Roots: Not verified.; Stems: Not verified.; Leaves: Not verified.; Flowers: Not verified.; Fruit: Not verified.
- Cultivation
- Not verified.
- Harvest and processing
- Sold as dried root, tea, tincture or capsule; extract content is not described in the sources read.
- Look-alikes and adulterants
- Name: Boneset (Eupatorium perfoliatum); Note: A different, related herb with its own page. Boneset has been shown to contain pyrrolizidine alkaloids; gravel root has not been shown either way.; Name: Spotted Joe-Pye weed (Eutrochium maculatum, formerly Eupatorium maculatum); Note: A close relative from which the alkaloid lycopsamine was isolated. Whether it is mixed with gravel root in trade is NOT verified.
- Sustainability and conservation
- Not assessed.
Traditional use and history history, not clinical proof
| Tradition or era | Documented use | Source |
|---|---|---|
| North American folk medicine | Used for urinary stones, urinary and prostate complaints, rheumatism, gout and fevers; the Cherokee used the root for rheumatism (earlier summary). | s-rxlist-gravel-root |
Traditional use shows how a plant was used. It does not show that a supplement works or is safe today.
What is inside, and how it may work
What the plant contains and how those compounds act in cells and animals. Laboratory and animal mechanisms are not proven effects in people.
Main compounds
| Compound | Family | Where it is concentrated | Activity studied | Level of evidence |
|---|---|---|---|---|
| Lycopsamine and intermedine (pyrrolizidine alkaloids) PubChem 107938 | pyrrolizidine alkaloid | not established for gravel root; found in relatives not reported for gravel root | Pyrrolizidine alkaloids can injure the liver after the body converts them to reactive forms. Lycopsamine was isolated from spotted Joe-Pye weed and is the main alkaloid group in boneset. Intermedine PubChem CID: 114843. 8 1 6 | Plant group (not gravel root) |
| Volatile oil components | terpenes and similar | leaves and stems not extracted | Studied in the lab for antifungal action. 3 | Laboratory research |
Mechanisms, receptors and pathways
| Target or pathway | Gene or receptor | What was found | Level |
|---|---|---|---|
| Liver activation of pyrrolizidine alkaloids | liver cytochrome P450 enzymes (general) | The 2011 Gynura case report states that PAs are activated by cytochrome P450 enzymes into reactive metabolites that bind proteins. This is for PAs in general, not gravel root. 4 | Human case report / animal (other plant) |
| Cell-culture toxicity | not established | Gravel root extract showed moderate killing of mouse neuroblastoma cells in a 374-extract screen (summary-only). 5 | In vitro |
Absorption, metabolism and elimination
- Absorption
- No data. RxList says toxins can absorb quickly through broken skin.
- Distribution
- RxList says PAs can pass into breast milk.
- Metabolism
- Not studied for gravel root. PAs in general are activated by liver enzymes.
- Elimination
- Not studied.
- Bioavailability
- Not established.
Isolated compounds versus whole extracts
No study compared whole root with any isolated compound. Teas, tinctures and decoctions of boneset carried high alkaloid levels, so common preparations should not be assumed safer. Gravel root preparations were not tested.
Nutritional composition
Not a food or nutrient source; no nutrient content was found.
7 not enough evidence
What is Gravel root good for?
What gravel root is traditionally used for and how strong the human evidence is. For every use below, no human study was found.
Benefits, one by one
Each card is a research question, not a promise. Tap a goal to filter. Open a card to see the studies, doses and limits.
Kidney and urinary stones
Not enough evidenceGravel root is best known as a folk remedy for 'gravel', the old word for small urinary stones. We found no human study, so we cannot say it helps. A stone or sudden urinary pain needs a doctor, not a herb.
1 studiesNot applicable. Dried root, tea and tinctures are the traditional for…
Studies, doses and limits
What the trials found
No human study found. RxList rates the evidence 'insufficient to rate'.
Results
No human results exist.
Effect sizes as reported
None.
Why this rating
No human or animal study of stones was found; only tradition and a consumer reference.
Form and dose studied
Not applicable. Dried root, tea and tinctures are the traditional forms; no study tested any of them.
Who was studied
None studied.
Limits
Search was by title and abstract in PubMed, not a full systematic search. RxList is not a primary source.
Why researchers looked
It is the use the herb is named for in North American folk medicine.
Traditional use
Used in North American folk medicine for urinary stones; the consumer reference RxList describes this use. This is tradition, not tested evidence.
Proposed mechanism Preliminary mechanism
No tested mechanism. RxList says it might work by reducing swelling (inflammation), without a study.
A proposed mechanism does not show that the effect happens in people.
Stone pain, blood in urine, fever with urinary pain, or being unable to pass urine need prompt medical care. The herb may carry liver-toxic alkaloids (see Safety).
Bladder, urethra and prostate infections, painful urination
Not enough evidenceTraditional healers used the root for urinary and prostate complaints. No trial exists. An infection is better treated by a doctor, because untreated urinary infections can reach the kidneys.
1 studiesNot applicable.
Studies, doses and limits
What the trials found
No human study found. RxList: insufficient evidence to rate.
Results
No results.
Effect sizes as reported
None.
Why this rating
No study of any kind on infections was found.
Form and dose studied
Not applicable.
Who was studied
None studied.
Limits
Consumer reference only.
Why researchers looked
Listed as a folk use alongside stones.
Traditional use
Folk use for bladder, urethra and prostate infections and painful urination (RxList).
Proposed mechanism Preliminary mechanism
None tested.
A proposed mechanism does not show that the effect happens in people.
Burning with fever, back pain or blood in the urine needs a doctor.
Increasing urine flow (diuretic) and the 'kidney root' name
Not enough evidenceThe plant is also called kidney root and is traditionally taken to increase urine flow. No study measured this in people. A real diuretic effect would matter for people taking lithium, so the consumer reference lists a lithium warning.
1 studiesNot applicable.
Studies, doses and limits
What the trials found
None.
Results
No results.
Effect sizes as reported
None.
Why this rating
No measurement of urine output was found.
Form and dose studied
Not applicable.
Who was studied
None studied.
Limits
Consumer reference only.
Why researchers looked
Listed as a traditional action (RxList lists increasing urine flow).
Traditional use
Traditional diuretic; the 'kidney root' name comes from this use.
Proposed mechanism Preliminary mechanism
Not tested. RxList says it may act as a diuretic and slow lithium clearance, without citing a study.
A proposed mechanism does not show that the effect happens in people.
People on lithium, or on water pills, should ask a pharmacist before using any diuretic herb.
Rheumatism, gout and fever
Not enough evidenceUsed traditionally for joint pain, gout and fevers, including fevers from malaria, dengue and typhus. No human study exists. Fever with these illnesses needs a doctor.
1 studiesNot applicable.
Studies, doses and limits
What the trials found
None. RxList: insufficient evidence to rate.
Results
No results.
Effect sizes as reported
None.
Why this rating
No study.
Form and dose studied
Not applicable.
Who was studied
None studied.
Limits
Consumer reference and earlier summary only.
Why researchers looked
Listed as folk uses.
Traditional use
Cherokee use for rheumatism is reported in our earlier summary; RxList lists the other uses. Not re-verified in a primary source.
Proposed mechanism Preliminary mechanism
None tested.
A proposed mechanism does not show that the effect happens in people.
A fever after travel to a malaria or dengue area is an emergency; do not self-treat with a herb.
Stomach acid, sweating, vomiting, 'tonic' uses
Not enough evidenceFolk uses also include reducing stomach acid, causing sweating or vomiting, and as a stimulant or tonic. None has been tested.
1 studiesNot applicable.
Studies, doses and limits
What the trials found
None.
Results
No results.
Effect sizes as reported
None.
Why this rating
No study.
Form and dose studied
Not applicable.
Who was studied
None studied.
Limits
Consumer reference only.
Why researchers looked
Listed as traditional actions.
Traditional use
RxList lists these as ways people use the herb.
Proposed mechanism Preliminary mechanism
None tested.
A proposed mechanism does not show that the effect happens in people.
Causing vomiting on purpose is not a safe self-treatment.
Cancer-cell killing in a dish
Not enough evidenceIn a 2009 screen of 374 plant extracts on mouse nerve-cancer cells, gravel root was reported, per our earlier summary, in a middle 'moderate' group. This is a cell-dish result only and does not show it treats cancer. The plant's alkaloids may themselves raise cancer concern.
1 studiesNot applicable.
Studies, doses and limits
What the trials found
None.
Results
The abstract does not mention gravel root; the 'moderate group' placement comes from our earlier summary of the paper and was not re-checked.
Effect sizes as reported
Not extracted.
Why this rating
Cell-dish toxicity only.
Form and dose studied
Not applicable.
Who was studied
Mouse cell line.
Limits
Lab only; detail summary-only.
Why researchers looked
Part of a general plant screen.
Traditional use
Not a traditional use.
Proposed mechanism Laboratory research
Cell-culture toxicity, not a treatment mechanism.
A proposed mechanism does not show that the effect happens in people.
Not a reason to take it.
Antifungal action of the leaf-and-stem oil
Not enough evidenceA 2020 lab study tested the essential oil from the above-ground parts of the plant on three fungi. The oil is a different product from the dried root sold as gravel root, and the abstract highlights a different plant's oil as the one with notable activity.
1 studiesNot applicable.
Studies, doses and limits
What the trials found
None.
Results
Modest activity per our earlier summary; the abstract itself does not report a gravel root number.
Effect sizes as reported
Not extracted.
Why this rating
Lab only, different plant part.
Form and dose studied
Not applicable.
Who was studied
Fungal cultures.
Limits
Lab only.
Why researchers looked
Part of a study of Native American medicinal plants.
Traditional use
Not a traditional root use.
Proposed mechanism Laboratory research
Lab antifungal screening only.
A proposed mechanism does not show that the effect happens in people.
Do not use essential oils as medicine on the skin or by mouth without professional advice.
Connections to the rest of health
How Gravel root connects to the rest of our health knowledge graph. Every link says what kind of connection it is. A safety link (for example to the liver) is a warning, not a benefit. A study that merely mentions a topic never creates a benefit link.
Explore every connection: goals, body systems, organs, symptoms, genes
B. Body systems
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Urinary System | Biological association | Not enough evidence | Studied for: Kidney and urinary stones Studied for: Bladder, urethra and prostate infections, painful urination | 7 |
| Musculoskeletal System | Biological association | Not enough evidence | Studied for: Rheumatism, gout and fever | 7 |
| Digestive System | Biological association | Not enough evidence | Studied for: Stomach acid, sweating, vomiting, 'tonic' uses | 7 |
E. Health conditions
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Pyrrolizidine alkaloid liver injury | Adverse effect or risk | Theoretical | Documented for other PA herbs; plausible but unproven for gravel root. Documented for other PA herbs; unproven for gravel root. Preparation or compound: Pyrrolizidine alkaloids (gravel root content not established) |
1 4 10 7 |
K. Biological pathways
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Pyrrolizidine alkaloid liver bioactivation | Preliminary mechanism | Human case report / animal (other plant) | General mechanism for PA herbs. | 4 |
L. Active compounds
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Lycopsamine and intermedine (pyrrolizidine alkaloids) | Biological association | Plant group (not gravel root) | Pyrrolizidine alkaloids can injure the liver after the body converts them to reactive forms. Lycopsamine was isolated from spotted Joe-Pye weed and is the main alkaloid group in boneset. Intermedine PubChem CID: 114843. Preparation or compound: not established for gravel root; found in relatives |
8 1 6 |
| Volatile oil components | Biological association | In vitro | Studied in the lab for antifungal action. Preparation or compound: leaves and stems |
3 |
Each connection is stored with the ingredient, the connected record, the kind of connection, the evidence status, the supporting studies, the preparation or compound involved, and a review date (last reviewed October 25, 2026).
The evidence
The research centre for Gravel root. Every record here was checked against PubMed or the publisher's page; we never list a study we have not verified.
Evidence by outcome
Bars show how many studies we found for each outcome, not how well it works. People are added up across trials only (reviews are not added, to avoid double counting).
How we rate evidence
High certainty
Several well-run trials or reviews agree; further research is unlikely to change the picture much.
Moderate certainty
Good trials point the same way, but some doubt remains.
Low certainty
Small, short or inconsistent trials. The finding could change with better research.
Very low certainty
Very little or very weak human data. Treat as a possibility only.
Mixed findings
Trials or reviews disagree with each other.
Not enough evidence
Not enough human research to say either way.
Evidence against
Good research found no benefit, or found harm.
We take the reviewers' own risk-of-bias and GRADE statements where they exist, and otherwise judge from study size, design, consistency, directness and whether a product matches what is sold. Many publications do not make evidence high. Method note: We searched PubMed and checked GBIF and PubChem for Irish moss. Most sources were abstracts only. No study is cited that we could not verify.
Study library: every study we checked 10
| Study | Design | People | Product, dose, length | Result |
|---|---|---|---|---|
| Colegate 2018 Potentially toxic pyrrolizidine alkaloids in Eupatorium perfoliatum and three related species. Implications for herbal use as boneset. Phytochem Anal · PMID 29968391 · DOI |
Laboratory analysis plant |
49 49 boneset samples plus related-species samples (lab analysis; no people) |
Methanol, hot water and aqueous ethanol extracts, tinctures, infusions and decoctions of boneset (Eupatorium perfoliatum) and three related species herb (boneset), related species not extracted not extracted · vs none |
All 49 boneset samples contained dehydropyrrolizidine alkaloids (0.0002-0.07% w/w), mostly lycopsamine and intermedine and their derivatives. Tinctures, hot-water infusions and decoctions had high concentrations. The authors urge caution until toxicity and cancer risk are better defined. The abstract does not name the three related species or say gravel root was tested. narrative; no pooled effect (not applicable) Methods, limits and fundingOutcomes: Presence and amount of dehydropyrrolizidine alkaloids Limitations: About boneset, a relative; gravel root was not shown to be tested. Abstract only. Funding and conflicts: Authors from USDA Poisonous Plant Research Laboratory and a herbal-standards body; no industry sponsor read in the abstract. Read: abstract |
| GBIF Secretariat 2026 GBIF Backbone Taxonomy: Eutrochium purpureum (L.) E.E.Lamont GBIF species match API · Source |
Database record plant |
Not applicable | Eutrochium purpureum (L.) E.E.Lamont whole plant not extracted not extracted · vs none |
GBIF key 3138192: ACCEPTED species, family Asteraceae. GBIF also lists Eupatorium purpureum Michx. (key 8311325) as a separate accepted entry, so the old name still appears in databases. narrative; no pooled effect (not applicable) Methods, limits and fundingOutcomes: Accepted name Limitations: API match 2026-10-25. NCBI taxonomy was not checked. Funding and conflicts: Public database. Read: database |
| Lawson 2020 Volatile Compositions and Antifungal Activities of Native American Medicinal Plants: Focus on the Asteraceae. Plants (Basel) · PMID 31963839 · DOI |
Laboratory study in-vitro |
Fungal cultures (no people) | Essential oil of Eutrochium purpureum aerial parts, tested against Aspergillus niger, Candida albicans and Cryptococcus neoformans leaves and stems (aerial parts), not root not extracted not extracted · vs none |
Nine Native American medicinal Asteraceae were tested. The abstract singles out another plant, Eupatorium serotinum, as the one with noteworthy activity. Our earlier summary recorded only modest activity for gravel root oil; that detail is from the full paper, which we did not re-open. narrative; no pooled effect (not applicable) Methods, limits and fundingOutcomes: Oil chemistry and in-vitro antifungal activity Limitations: Lab only. Oil from above-ground parts, not the root that is sold. Funding and conflicts: Not read. Read: abstract (detail summary-only) |
| Lin 2011 Hepatic sinusoidal obstruction syndrome associated with consumption of Gynura segetum. J Hepatol · PMID 21146894 · DOI |
Case report with lab |
1 1 patient plus rats |
Gynura segetum (a pyrrolizidine-alkaloid herb mistaken for another herb) herb not extracted not extracted · vs none |
One liver-biopsy-confirmed case of hepatic sinusoidal obstruction syndrome after taking a PA-containing herb. Reports that over 8000 PA-related cases have been reported worldwide. Shows how pyrrolizidine alkaloids injure the liver. narrative; no pooled effect (not applicable) Methods, limits and fundingOutcomes: Liver injury, pyrrole-protein adducts Limitations: A different plant (Gynura), used here only to explain the type of liver injury that PAs cause. Authors' author list shortened in our record. Funding and conflicts: Not read. Read: abstract |
| Mazzio 2009 In vitro screening for the tumoricidal properties of international medicinal herbs. Phytother Res · PMID 18844256 · DOI |
Laboratory study in-vitro |
Mouse neuroblastoma cell culture | 374 plant extracts, including (per our earlier summary) gravel root not stated in abstract not extracted not extracted · vs none |
Screening of 374 extracts on one cancer cell line. The abstract does not mention gravel root; our earlier summary placed it in a 'moderate' group, which came from the paper's tables and was not re-checked. narrative; no pooled effect (not applicable) Methods, limits and fundingOutcomes: Cell killing in culture Limitations: Cell culture only; killing cells in a dish is not a treatment effect. The gravel root placement is summary-only. Funding and conflicts: Not read. Read: abstract (gravel root detail summary-only) |
| PubChem (NCBI) 2026 PubChem: lycopsamine (CID 107938) and intermedine (CID 114843) PubChem PUG REST · Source |
Database record not applicable |
Not applicable | Lycopsamine, intermedine (pyrrolizidine alkaloids) not applicable not extracted not extracted · vs none |
Lycopsamine CID 107938, formula C15H25NO5; intermedine CID 114843, formula C15H25NO5 (matched by name on 2026-10-25). narrative; no pooled effect (not applicable) Methods, limits and fundingOutcomes: Compound identity Limitations: Identity check only. Funding and conflicts: Public database. Read: database |
| RxList (Natural Medicines-style consumer monograph) 2026 Gravel root vitamins and supplements (consumer drug reference page) RxList · Source |
Consumer reference |
General public | Gravel root (Eupatorium purpureum) root, bulb and above-ground parts (as listed) not extracted not extracted · vs none |
Says gravel root is used for urinary and kidney stones, bladder, urethra and prostate infections, painful urination, rheumatism, gout and fever, and rates every one 'insufficient evidence to rate'. Warns it contains hepatotoxic pyrrolizidine alkaloids that may block liver veins and cause liver damage, cancer and birth defects. Rates uncertified products and use on broken skin as 'likely unsafe'; advises avoiding it in pregnancy and breastfeeding even if certified; warns of allergy in people allergic to ragweed and other daisy-family plants. Moderate interactions listed for lithium and for liver-enzyme-inducing medicines. narrative; no pooled effect (not applicable) Methods, limits and fundingOutcomes: Uses, safety, pregnancy, interactions Limitations: A consumer reference, not an agency or a primary study. It gives no sources for its alkaloid statement in the text we read. Its wording suggests the alkaloid risk is assumed from the plant group. Funding and conflicts: Commercial publisher; no product promoted. Read: full-text |
| Wiedenfeld 2009 Lycopsamine and cumambrin B from Eupatorium maculatum. Pharmazie · PMID 19618682 |
Laboratory isolation plant |
Plant material (no people) | Eupatorium maculatum L. (spotted Joe-Pye weed, now usually Eutrochium maculatum) plant material, part not stated in abstract not extracted not extracted · vs none |
The pyrrolizidine alkaloid lycopsamine and the guaianolide cumambrin B were isolated from Eupatorium maculatum, and their structures worked out. narrative; no pooled effect (not applicable) Methods, limits and fundingOutcomes: Isolation of compounds Limitations: A close Joe-Pye weed relative, not gravel root. Abstract only; no toxicity testing. Funding and conflicts: Not read. Read: abstract |
| Zhao 1987 A comparative study on the pyrrolizidine alkaloid content and the pattern of hepatic pyrrolic metabolite accumulation in mice given extracts of Eupatorium plant species, Crotalaria assamica and an Indian herbal mixture. Am J Chin Med · PMID 3687841 · DOI |
Animal study animal |
Mice | Extracts of three Asian Eupatorium species (E. japonicum, E. fortunei, E. chinense), compared with a hepatotoxic Indian herbal mixture and Crotalaria assamica herb extracts not extracted not extracted · vs none |
Those three Eupatorium species had very low alkaloid levels compared with the hepatotoxic comparators, and did not cause pyrrole-metabolite build-up in mouse livers, including with chronic decoction dosing. narrative; no pooled effect (not applicable) Methods, limits and fundingOutcomes: Pyrrolizidine alkaloid content and liver pyrrole-metabolite build-up Limitations: Different Eupatorium species from Asia, not North American gravel root. Mice only. Shows that alkaloid levels differ a lot between species, so one species cannot stand in for another. Funding and conflicts: Not read. Read: abstract |
| Zhu 2021 Tu-San-Qi (Gynura japonica): the culprit behind pyrrolizidine alkaloid-induced liver injury in China. Acta Pharmacol Sin · PMID 33154553 · DOI |
Narrative review |
About 2,214 reported cases in China | Gynura japonica (PA-producing herb) herb not extracted not extracted · vs none |
Reviews about 2,214 PA-herb cases of hepatic sinusoidal obstruction syndrome, which causes liver enlargement, high bilirubin and fluid in the abdomen, and says over half of Chinese cases come from this one PA herb. narrative review of case reports (not applicable) Methods, limits and fundingOutcomes: Clinical features and outcomes of PA-induced liver injury Limitations: Different plant. It shows how serious PA liver injury can be but says nothing about gravel root. Author list shortened. Funding and conflicts: Not read. Read: abstract |
What we do not know yet
- No human trial of gravel root for any use was found in PubMed (a title/abstract search for Eupatorium purpureum or Eutrochium purpureum returned only a handful of lab and chemistry papers).
- No study measured whether gravel root helps, prevents or dissolves kidney or urinary stones.
- The pyrrolizidine alkaloid content of gravel root root itself was not found in any source read.
- Only abstracts were read for papers other than RxList.
- LiverTox, EMA/HMPC, NCCIH and LactMed were not opened.
How new research is added
New studies are found by a saved PubMed search and are placed in a review queue. A person reads each one before it changes any evidence rating or safety wording.
Lab markers
What changed in blood or saliva tests during trials. A changed number is not the same as feeling or being healthier, and we give no "normal ranges".
Safety
What studies and official sources say about side effects, medicines and who should check first. Each point shows what kind of evidence it comes from.
Main points to know 3
- Possible liver-toxic alkaloids: gravel root itself is not well tested. Gravel root belongs to the Eupatorium group, and several relatives contain pyrrolizidine alkaloids, which can cause serious liver injury (blocked small liver veins, called sinusoidal obstruction syndrome). Boneset (Eupatorium perfoliatum), a close relative, contained these alkaloids in all 49 samples tested, with high levels in tinctures, teas and decoctions. A relative called spotted Joe-Pye weed gave lycopsamine, one of them. We did NOT find any analysis of the alkaloids in Eutrochium purpureum (gravel root) root itself, so how much it contains is unknown. A different set of Asian Eupatorium species had very low levels in an old mouse study, so levels clearly vary by species. Until gravel root is tested, treat it as possibly liver-toxic. RxList rates uncertified products 'likely unsafe'. Laboratory analysis 1 8 9 7
- Pregnancy and breastfeeding: avoid. Pyrrolizidine alkaloids are linked to birth defects and can pass into breast milk, according to RxList, which advises avoiding all gravel root in pregnancy and breastfeeding. This is a consumer reference, not an agency ruling, and no gravel root pregnancy study exists. Other 7
- Kidney stones and urinary pain need medical care. Gravel root is mainly used for stones and urinary infections. Both can harm the kidneys if untreated, and no study shows the herb helps. Do not use it in place of a doctor, especially with fever, back pain, blood in the urine or inability to pass urine. Other 7
Side effects 3
| Effect | How often | Severity and recovery | Evidence |
|---|---|---|---|
| Liver injury: hepatic sinusoidal obstruction syndrome (liver enlargement, high bilirubin, fluid in the belly) Documented for other pyrrolizidine-alkaloid herbs (Gynura species in China, about 2,214 reported cases in one review). No case report attributed to gravel root was found; the link to gravel root rests on its plant group and on RxList's warning. | Not established | can be severe or fatal varies; see a doctor | Case report 4 10 |
| Possible cancer and birth-defect risk from pyrrolizidine alkaloids Raised by RxList and by the boneset authors, who say toxicity and cancer risk of these alkaloids still need defining. | Not established | unknown for gravel root not applicable | Other 7 1 |
| Allergic reaction in people allergic to ragweed, daisies, chrysanthemums, marigolds and other daisy-family plants Cross-reactivity warning only; no case found. | Not established | mild to serious usually stops when avoided | Other 7 |
Liver
No report of liver injury from gravel root itself was found, and we found no LiverTox entry for it. But its plant group contains liver-toxic pyrrolizidine alkaloids. Boneset samples all contained them, and the herb's relatives show the pattern, while some Asian Eupatorium species had very little. Because gravel root has not been tested, its risk is unknown, and RxList treats it as likely unsafe unless certified free of these alkaloids. People with liver disease should avoid it. 1 9 4 10 7
How often. Unknown.
Monitoring. No agency monitoring advice was found.
This is a safety connection. It is not evidence that Gravel root supports liver health.
Medicines and supplements 3
| With | Why it matters | Importance | Evidence | What to do |
|---|---|---|---|---|
| Lithium prescription | RxList says gravel root may act as a diuretic and slow lithium clearance, raising lithium levels. | Rated moderate by RxList; lithium has a narrow safe range. | Pharmacological theory Low certainty 7 | Ask a pharmacist or doctor before use. |
| Liver-enzyme-inducing medicines (carbamazepine, phenobarbital, phenytoin, rifampin, rifabutin) prescription | RxList says these may speed breakdown of gravel root compounds and so raise the toxicity of its harmful alkaloids. | Rated moderate by RxList; theoretical. | Pharmacological theory Low certainty 7 | Ask a pharmacist or doctor before use. |
| Other liver-affecting herbs, alcohol and liver-toxic medicines other | Added strain on the liver is a theoretical concern given the alkaloid risk. | Not studied. | Pharmacological theory Very low certainty 7 | Ask a pharmacist. |
Who should check first 7
| Situation | Advice | Evidence |
|---|---|---|
| Pregnancy or breastfeeding | Avoid. | Other 7 |
| Liver disease, or a history of liver problems | Avoid; ask your doctor. | Other 7 1 |
| Taking lithium or enzyme-inducing seizure or TB medicines | Ask a pharmacist first. | Pharmacological theory 7 |
| Allergy to ragweed or other daisy-family plants | Avoid or ask a doctor. | Other 7 |
| Children | No safety data; avoid. | Other 7 |
| Kidney stones, urinary infections, blood in urine | See a doctor; do not self-treat with this herb. | Other 7 |
| Broken skin | Do not apply; RxList warns toxins can absorb quickly. | Other 7 |
Overdose, product quality and regulators
Summary. The main concern is the pyrrolizidine alkaloid group. Whether gravel root root contains them, and how much, is not established by any source we read.
Animal. One old mouse study of three Asian Eupatorium species found little liver pyrrole build-up; it does not cover gravel root.
Human doses studied. Not given. No safe human amount has been established.
High dose or long term signals. The boneset authors raise long-term low-level exposure as an international concern.
Overdose response. Not described for gravel root. Seek urgent care for the signs listed.
Genotoxicity. Not found for gravel root.
Toxic plant parts. Not established. RxList lists root, bulb and above-ground parts as used.
No contamination or adulteration testing of gravel root products was found. Joe-Pye weed relatives and boneset are sometimes confused, and alkaloid levels differ a lot between species and chemotypes.
Species variation in alkaloids. Boneset samples ranged from 0.0002 to 0.07% alkaloid by weight, and the authors suggest different chemotypes, hybridisation or contamination with related species. 1
| Body | Action | Date |
|---|---|---|
| RxList (consumer reference) (United States) | Gravel root: insufficient evidence for all uses; uncertified products likely unsafe; avoid in pregnancy and breastfeeding. source | 2026-10-25 |
When to get medical help
- Yellow skin or eyes, dark urine, pale stools, or a swollen belly after taking the herb
- Sudden belly pain, nausea, vomiting or great tiredness
- Severe back or side pain, fever with urinary pain, blood in the urine, or not being able to pass urine
- Rash, swelling of the face or trouble breathing (allergy)
Stop the supplement and contact a clinician or emergency service. In the US, Poison Control is 1-800-222-1222.
General information only, not medical advice. Ask a clinician or pharmacist before use, especially with medicines, in pregnancy or with a health condition. See the Natural Remedy Safety guide.
Frequently asked questions
What is gravel root?
Does gravel root dissolve kidney stones?
No study shows that. Evidence is rated insufficient. Stones can block the urinary tract and need medical care.
Is gravel root safe for the liver?
Do all Eupatorium plants contain the same alkaloids?
Can I take it while pregnant or breastfeeding?
No. A consumer reference says to avoid it, citing possible birth defects and passage into breast milk. No gravel root study exists.
What medicines interact with it?
RxList lists lithium and enzyme-inducing medicines such as carbamazepine, phenobarbital, phenytoin, rifampin and rifabutin. These are theoretical, moderate-level warnings. Ask a pharmacist.
Is it the same as boneset?
No. Boneset is Eupatorium perfoliatum. They are related and sometimes share the name 'purple boneset' or similar, but they are different plants. See our boneset page.
Is there any human research on it?
What signs of liver trouble should I watch for?
Can I put it on my skin?
RxList says use on broken skin is likely unsafe and advises avoiding it on unbroken skin too.
I am allergic to ragweed. Is it a problem?
It can be. Gravel root is in the daisy family with ragweed, and RxList warns of cross-reaction.
Why is it called kidney root?
Because of its traditional use for the urinary tract and as a diuretic. That is tradition; no study confirms a kidney benefit.
Should I use it for kidney stones or urinary pain?
See a doctor first. Stones and infections can harm the kidneys, and a herb with an unknown liver risk is a poor trade. Ask your doctor or pharmacist about any herb.
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Editorial transparency
- Written by
- AlternativeMed editorial team. Research compiled with AI assistance, then checked against PubMed records.
- Medical review
- None. This page has not been reviewed by a physician or pharmacist.
- First published
- 2026-10-25
- Last substantive update
- 2026-10-25
- How we research
- We searched PubMed and checked GBIF and PubChem for Irish moss. Most sources were abstracts only. No study is cited that we could not verify.
- How we rate evidence
- See "How we rate evidence" in the Evidence tab.
- Independence
- No product is promoted on this page. No affiliate links are shown. If one is added later it will be labelled and kept apart from the evidence.
Sources 10
Each source was opened and checked. Where we read only the abstract, it says so. The small numbers in the text point here.
- Colegate SM, Upton R, Gardner DR, Panter KE, Betz JM. Potentially toxic pyrrolizidine alkaloids in Eupatorium perfoliatum and three related species. Implications for herbal use as boneset.. Phytochem Anal. 2018. PMID 29968391. DOI 10.1002/pca.2775. (abstract)
- GBIF Secretariat. GBIF Backbone Taxonomy: Eutrochium purpureum (L.) E.E.Lamont. GBIF species match API. 2026. (database)
- Lawson SK, Sharp LG, Powers CN, McFeeters RL, Satyal P, Setzer WN. Volatile Compositions and Antifungal Activities of Native American Medicinal Plants: Focus on the Asteraceae.. Plants (Basel). 2020. PMID 31963839. DOI 10.3390/plants9010126. (abstract (detail summary-only))
- Lin G, Wang JY, Li N, Li M, Gao H, Ji Y, Zhang F, Wang H, Zhou Y, Ye Y, Xu HX, Zheng J. Hepatic sinusoidal obstruction syndrome associated with consumption of Gynura segetum.. J Hepatol. 2011. PMID 21146894. DOI 10.1016/j.jhep.2010.07.031. (abstract)
- Mazzio EA, Soliman KF. In vitro screening for the tumoricidal properties of international medicinal herbs.. Phytother Res. 2009. PMID 18844256. DOI 10.1002/ptr.2636. (abstract (gravel root detail summary-only))
- PubChem (NCBI). PubChem: lycopsamine (CID 107938) and intermedine (CID 114843). PubChem PUG REST. 2026. (database)
- RxList (Natural Medicines-style consumer monograph). Gravel root vitamins and supplements (consumer drug reference page). RxList. 2026. (full-text)
- Wiedenfeld H, Hosch G, Roeder E, Dingermann T. Lycopsamine and cumambrin B from Eupatorium maculatum.. Pharmazie. 2009. PMID 19618682. (abstract)
- Zhao XL, Chan MY, Kumana CR, Ogle CW. A comparative study on the pyrrolizidine alkaloid content and the pattern of hepatic pyrrolic metabolite accumulation in mice given extracts of Eupatorium plant species, Crotalaria assamica and an Indian herbal mixture.. Am J Chin Med. 1987. PMID 3687841. DOI 10.1142/S0192415X87000084. (abstract)
- Zhu L, Zhang C, Li C, Chen X, et al.. Tu-San-Qi (Gynura japonica): the culprit behind pyrrolizidine alkaloid-induced liver injury in China.. Acta Pharmacol Sin. 2021. PMID 33154553. DOI 10.1038/s41401-020-00553-9. (abstract)