Infusion
Crushed dried leaf steeped in boiling water — the most traditional and widely used preparation.
Dried Leaf · Tea
French Pharmacopoeia · List A
Biological Overview
Boldo is a small evergreen, dioecious tree strictly confined to the Mediterranean-climate region of Chile. Its grayish-green, oval leaves are hard, brittle, and rough to the touch, with edges that curl slightly toward the underside.
Life CycleEvergreen tree
HabitatCentral Chile
Essential OilMin. 2% (ascaridole)
Marker AlkaloidBoldine
Botanical Classification
Taxonomy & Identification
- Latin Name
- Peumus boldus Mol.
- Synonym
- Peumus boldo
- Family
- Monimiaceae
- Common Names
- Boldo, Boldu
- Parts Used
- Dried leaf
- Habitat
- Mediterranean-climate zone, central Chile
- Marker Compound
- Boldine
Ethnobotany & Traditional Use
History & Tradition
The common name "boldo" comes from the Mapuche word foḻo. The tree is endemic to Chile, where its leaves have long been used in traditional medicine for liver and gallbladder complaints, a use that spread across Latin America.
The primary phytotherapy literature notes one distinctive sensory detail: the aromatic character of the crushed leaves recalls lemon balm and mint.
⚠ Species Identification
True boldo (Peumus boldus) is frequently confused with "false boldo" (Plectranthus ornatus), an unrelated plant sold under similar common names but with a different safety and efficacy profile.
The Key Molecule
Boldine — Deep Dive
The principal aporphine alkaloid in boldo leaves, and the compound behind most of its documented pharmacology.
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Vascular Endothelial Protection
Protects the vascular endothelium against oxidative stress, with implications for hypertension and diabetes research.[6]
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Selective Alpha-1A Adrenoceptor Affinity
Boldine and its derivatives (glaucine, predicentrine) show subtype-selective affinity for alpha-1A adrenoceptors, a structural basis for the plant's antispasmodic action.[13]
⚠ Extract Type Matters
Boldine content isn't the only thing to check — so is ascaridole.
Boldo essential oil contains ascaridole, which is hepatotoxic in concentrated amounts. Because ascaridole has low water solubility, the European Medicines Agency's herbal monograph endorses aqueous dry extracts and infusions, but not ethanolic tinctures or fluid extracts, which tend to carry higher ascaridole levels.
Pharmaceutical Preparations
Parts Used & Available Forms
Only the dried leaf of boldo is used medicinally.
Dry Extract (Aqueous)
A 5:1 aqueous dry extract — the form specifically endorsed by the EU herbal monograph due to lower ascaridole content.
Aqueous · EU-Endorsed
Mother Tincture
A traditional alcoholic leaf tincture — note that ethanolic preparations are not EMA-endorsed due to higher ascaridole levels.
Ethanolic · Traditional Only
Clinical Dosimetry
Dosages
Two figures appear in the literature — the source monograph's general infusion amount, and the more detailed European Medicines Agency herbal monograph.
Phytochemistry
Composition
Boldo's chemistry centers on aporphine alkaloids dominated by boldine, alongside an essential oil that requires safety attention.
Aporphine Alkaloids
BoldinePrincipal alkaloid; hepatoprotective, antioxidant, anti-inflammatory
Major
IsoboldineCo-occurring aporphine derivative
Minor
Isocorydine & NorisocorydineAporphine alkaloid derivatives
Minor
Laurotetanine & LaurolitsineMinor aporphine-type alkaloids
Trace
Essential Oil & Other Constituents
Essential Oil (min. 2%)Monoterpenes: limonene, β-pinene, paracymene, linalool, 1,8-cineole, camphor
Present
AscaridoleMonoterpene peroxide; hepatotoxic in concentrated amounts — see Safety
Caution
Flavonol GlycosidesDerivatives of rhamnetol, isorhamnetol, kaempferol
Present
CatechinsPolyphenolic antioxidant compounds
Present
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Choleretic (Disputed)
Traditionally described as increasing bile secretion — however, a review by the pharmacologist Fleurentin was unable to reproduce this effect, so it remains an unconfirmed traditional claim rather than an established finding.
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Hepatoprotective
Inhibits lipid peroxidation and protects the liver against carbon tetrachloride, cisplatin, and tert-butyl hydroperoxide toxicity; stimulates glutathione S-transferase activity.[1][2][3][4][5]
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Anti-Atherosclerotic
Boldine protects the vascular endothelium against oxidative stress.[6]
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Anti-Inflammatory
Boldine protects biological systems against peroxidative free-radical damage and demonstrates anti-inflammatory and antipyretic activity.[7][8]
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Antispasmodic
Relaxant effect on smooth muscle via an anticholinergic mechanism.[9]
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Antioxidant
Free-radical scavenging and broader antioxidant/health-promoting properties documented for boldine.[10]
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Hematological Cytoprotection
Protects red blood cells against free-radical–induced lysis.[11]
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Neuroprotective
Antioxidant and pro-oxidant properties studied on hippocampal slices exposed to oxygen-glucose deprivation.[12]
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Alpha-1A Adrenoceptor Selectivity
Boldine and its derivatives (glaucine, predicentrine) show subtype selectivity for the alpha-1A adrenoceptor.[13]
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Anthelmintic (Vermifuge)
Documented traditional use as a vermifuge in the primary phytotherapy literature.
Clinical Applications
Clinical Indications
Traditional and clinically studied applications drawn from the primary phytotherapy literature.
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Biliary Insufficiency
Non-Lithiasic
- Non-lithiasic biliary insufficiency: sluggish bile flow without gallstone obstruction.
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Gallbladder Disorders
Cholecystopathies
- Cholecystopathies: general gallbladder disorders, per the primary phytotherapy literature.
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Smooth Muscle Spasms
Alpha-1A Adrenoceptors
- Smooth-muscle spasms: mediated via alpha-1A adrenoceptors. [13]
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Prostatic Disorders
Unconfirmed
- Prostatic disorders: the primary phytotherapy literature lists this with an explicit question mark — an open question, not a confirmed indication.
Pharmacodynamics
Mode of Action
Documented and presumed mechanisms underlying boldo's antispasmodic and hepatoprotective effects.
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Anticholinergic / Parasympatholytic Action
A parasympatholytic, anticholinergic mechanism underlies boldo's smooth-muscle relaxant effect.
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Lipid Peroxidation Inhibition
Inhibition of lipid peroxidation is the proposed basis for boldine's hepatoprotective action.[1]
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Alpha-1A Adrenoceptor Selectivity
Boldine, glaucine, and predicentrine show subtype-selective affinity for the alpha-1A adrenoceptor, a structural basis for antispasmodic activity.[13]
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Glutathione S-Transferase Stimulation
Stimulates glutathione S-transferase activity, supporting the liver's own detoxification capacity.[5]
Clinical Safety
Safety, Interactions & Precautions
Boldo's essential oil content and alkaloid profile require attention to specific contraindications.
Adverse Effects & Cautions
- Gallstone obstruction: contraindicated where biliary calculi could obstruct bile flow.
- Long-term toxicity: hydroalcoholic leaf extract and boldine produced abortive and teratogenic effects and altered blood transaminase and urea levels in rats, without histological changes. [14]
- Ascaridole content: the essential oil's ascaridole is hepatotoxic in concentrated amounts — favor aqueous preparations over ethanolic ones.
- Behavioral effects: a case report described hallucinations and behavioral impairment following consumption of boldo leaf infusions. [16]
Drug Interactions
- Warfarin: a suspected interaction case has been reported with a boldo-fenugreek combination. [15]
- Tacrolimus: a case report documented subtherapeutic tacrolimus levels in a renal transplant patient taking boldo, which normalized after discontinuation. [17]
- Blood clotting: boldo may slow blood clotting, raising a general caution around concurrent anticoagulant or antiplatelet use.
Clinical Disclaimer: This monograph is for educational and professional reference only. It does not constitute medical advice, diagnosis, or treatment guidance. Always consult a qualified healthcare provider before initiating any phytotherapeutic regimen, particularly if you have gallstones, are pregnant, take anticoagulants or immunosuppressants, or have existing health conditions.
Common Questions
Frequently Asked Questions
What is boldo used for?
Boldo (Peumus boldus) is traditionally used for non-lithiasic biliary insufficiency, gallbladder disorders, and smooth-muscle spasms of the gastrointestinal tract. It is also studied for hepatoprotective and antioxidant effects via its alkaloid boldine.
What is boldine?
Boldine is the principal aporphine alkaloid in boldo leaves and the compound most responsible for its documented hepatoprotective, antioxidant, anti-inflammatory, and vascular-protective effects.
Does boldo really stimulate bile secretion?
This is disputed. Boldo is traditionally described as choleretic, but a review by the pharmacologist Fleurentin was unable to reproduce this effect, so it should be considered an unconfirmed traditional claim rather than an established finding.
What is the recommended dosage of boldo?
Sources vary. The European Medicines Agency's herbal monograph cites an infusion of 1 to 2 g taken 2 to 3 times daily, or an aqueous dry extract (5:1) of up to 400 mg twice daily. Always confirm dosing with a qualified healthcare provider.
Is boldo safe for long-term use?
Caution is warranted. Animal studies found that hydroalcoholic leaf extract and boldine produced abortive and teratogenic effects and altered blood transaminase and urea levels, even without histological changes. It is also contraindicated in gallstone obstruction.
Can boldo be confused with another plant?
Yes. Boldo is frequently confused with "false boldo" (Plectranthus ornatus), an unrelated plant sold under similar common names but with a different safety and efficacy profile.
Does boldo interact with medications?
Yes. Case reports describe a possible interaction with warfarin and a documented case of subtherapeutic tacrolimus levels in a renal transplant patient taking boldo. It may also slow blood clotting.
Why doesn't the EMA endorse boldo tinctures?
Boldo essential oil contains ascaridole, which is hepatotoxic in concentrated amounts. Ethanolic tinctures and fluid extracts tend to carry higher ascaridole levels than aqueous preparations, so the European Medicines Agency's herbal monograph endorses only aqueous dry extracts and infusions.
Can boldo help with prostate issues?
This is an open question rather than a confirmed indication. The primary phytotherapy literature lists prostatic disorders with a question mark, signaling that this use is not well established.
Primary Literature
Bibliography
↑
1.
Cederbaum AI, Kukiełka E, Speisky H. Inhibition of rat liver microsomal lipid peroxidation by boldine. Biochem Pharmacol. 1992;44(9):1765-1772.
PubMed PMID:1333206 →
↑
2.
Lanhers MC, Joyeux M, Soulimani R, Fleurentin J, Sayag M, Mortier F, Younos C, Pelt JM. Hepatoprotective and anti-inflammatory effects of a traditional medicinal plant of Chile, Peumus boldus. Planta Med. 1991;57(2):110-115.
PubMed PMID:1891491 →
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3.
Fernández J, Lagos P, Rivera P, Zamorano-Ponce E. Effect of boldo (Peumus boldus Molina) infusion on lipoperoxidation induced by cisplatin in mice liver. Phytother Res. 2009;23(7):1024-1027.
PubMed PMID:19145575 →
↑
4.
Bannach R, Valenzuela A, Cassels BK, Nunez-Vergara LJ, Speisky H. Cytoprotective and antioxidant effects of boldine on tert-butyl hydroperoxide-induced damage to isolated hepatocytes. Cell Biol Toxicol. 1996;12(2):89-100.
PubMed PMID:8738478 →
↑
5.
Kubínová R, Machala M, Minksová K, Neca J, Suchý V. Chemoprotective activity of boldine: modulation of drug-metabolizing enzymes. Pharmazie. 2001;56(3):242-243.
PubMed PMID:11265593 →
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6.
Lau YS, Ling WC, Murugan D, Mustafa MR. Boldine ameliorates vascular oxidative stress and endothelial dysfunction: therapeutic implication for hypertension and diabetes. J Cardiovasc Pharmacol. 2015;65(6):522-531.
PubMed PMID:25469805 →
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7.
Schmeda-Hirschmann G, Rodriguez JA, Theoduloz C, Astudillo SL, Feresin GE, Tapia A. Free-radical scavengers and antioxidants from Peumus boldus Mol. ("Boldo"). Free Radic Res. 2003;37(4):447-452.
PubMed PMID:12747739 →
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8.
Backhouse N, Delporte C, Givernau M, Cassels BK, Valenzuela A, Speisky H. Anti-inflammatory and antipyretic effects of boldine. Agents Actions. 1994;42(3-4):114-117.
PubMed PMID:7879695 →
↑
9.
Goetz P. Insuffisance biliaire (non lithiasique). Formation Continue Phytothérapie Clinique. Phytothérapie. 2011;9:172.
DOI:10.1007/s10298-011-0633-6 →
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10.
O'Brien P, Carrasco-Pozo C, Speisky H. Boldine and its antioxidant or health-promoting properties. Chem Biol Interact. 2006;159(1):1-17.
PubMed PMID:16221469 →
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11.
Jiménez I, Garrido A, Bannach R, Gotteland M, Speisky H. Protective effects of boldine against free radical-induced erythrocyte lysis. Phytother Res. 2000;14(5):339-343.
PubMed PMID:10925398 →
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12.
Konrath EL, Santin K, Nassif M, Latini A, Henriques A, Salbego C. Antioxidant and pro-oxidant properties of boldine on hippocampal slices exposed to oxygen-glucose deprivation in vitro. Neurotoxicology. 2008;29(6):1136-1140.
PubMed PMID:18590764 →
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13.
Madrero Y, Elorriaga M, Martinez S, Noguera MA, Cassels BK, D'Ocon P, Ivorra MD. A possible structural determinant of selectivity of boldine and derivatives for the alpha 1A-adrenoceptor subtype. Br J Pharmacol. 1996;119(8):1563-1568.
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14.
Almeida ER, Melo AM, Xavier H. Toxicological evaluation of the hydro-alcohol extract of the dry leaves of Peumus boldus and boldine in rats. Phytother Res. 2000;14(2):99-102.
PubMed PMID:10685105 →
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15.
Lambert JP, Cormier J. Potential interaction between warfarin and boldo-fenugreek. Pharmacotherapy. 2001;21(4):509-512.
DOI:10.1592/phco.21.5.509.34492 →
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16.
Chaboussant PJ, Gagez AL, Graber M, et al. Behavioural impairments and hallucinations after consumption of boldo leaf infusions. Therapie. 2014;69(5):465-467.
PubMed PMID:25230279 →
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17.
Carbajal R, Yisfalem A, Pradhan N, Baumstein D, Chaudhari A. Case report: boldo (Peumus boldus) and tacrolimus interaction in a renal transplant patient. Transplant Proc. 2014;46(7):2400-2402.
PubMed PMID:24981811 →
Additional Reference Literature
Speisky H, Cassels BK. Boldo and boldine: an emerging case of natural drug development. Pharmacol Res. 1994;29(1):1-12. PubMed PMID:8202440 →
Rakotonanahary Maldonado M. Peumus boldus M.: de la botanique à la thérapeutique — état des connaissances en 2012. Doctoral thesis, Université Grenoble. 95 p. Full text →
Maia Mariano X, Mello de Souza WF, Rocha CB, Alves Moreira RF. Bioactive volatile fraction of Chilean boldo (Peumus boldus Molina) — an overview. J Essent Oil Res. 2019;31(6):474-486. DOI:10.1080/10412905.2019.1617797 →
European Medicines Agency, Committee on Herbal Medicinal Products (HMPC). Community herbal monograph on Peumus boldus Molina, folium. 2009. Full monograph →