Plant Comparison

Andrographis vs Pleurisy Root

A side-by-side comparison of two medicinal plants — every documented constituent, action, use, safety note and cited source, assembled automatically from the Omnia Sana database.

First plant
Second plant
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Plant AAndrographisAndrographis paniculataAcanthaceaeFull monograph →
Plant BPleurisy RootAsclepias tuberosaApocynaceaeFull monograph →

At a glance

Andrographis and Pleurisy Root: they share 5 indicated uses (arthritis / joint pain, cold & flu, fever, …); 1 pharmacological action in common.

AndrographisPleurisy Root
Constituents32
Pharmacological actions63
Indicated uses108
Safety notes32
Cited sources1714
Indicated uses
Only Andrographis
Cancer (anticancer research)Immune supportInfection (general)Sore throatWounds
Shared (5)
Arthritis / joint painCold & fluFeverInflammation (general)Skin irritation
Only Pleurisy Root
BronchitisCoughRespiratory support
Pharmacological actions
Only Andrographis
Anticancer (preclinical)AntimicrobialAntipyretic (reduces fever)AntiviralImmunomodulator / immune support
Shared (1)
Anti-inflammatory
Only Pleurisy Root
DiaphoreticExpectorant

Evidence face-off — shared uses

ConditionAndrographisPleurisy RootVerdict
Arthritis / joint pain5/101/10Stronger for Andrographis
Cold & flu8/101/10Stronger for Andrographis
Fever2/101/10Comparable evidence
Inflammation (general)5/101/10Stronger for Andrographis
Skin irritation5/102/10Stronger for Andrographis

Evidence scores (1–10) are computed from the tier of each cited source. “Comparable” means the two scores are within one point. Follow a score to its detailed sources.

Key Constituents

Diterpenoid lactones[2, 3, 10, 11]

Andrographolide is the principal active compound; also neoandrographolide and deoxyandrographolide.

Flavonoids[11]

Antioxidant and anti-inflammatory constituents.

Flavonoids
Polyphenols and other phenolics[11]

Contribute to antioxidant activity.

Phenolic compounds
Cardiac glycosides (cardenolides such as asclepin, calactin and calotropin)[11, 12]

Heart-active compounds that make dosing and safety critical.

Glycosides
Flavonoids and amino acids[12]

Supporting constituents of the root.

Flavonoids

Pharmacological Actions

Anti-inflammatory[2, 7, 9, 10, 11]
Anticancer (preclinical)[14, 15, 16]

Andrographolide, the principal diterpene lactone of Andrographis paniculata, suppresses proliferation and induces apoptosis across breast, lung, colon, cervical, hepatic and haematological cancers via NF-kappaB and PI3K/Akt inhibition (preclinical).

Antimicrobial[1, 6, 8, 10, 11]

Antimicrobial and antiviral

Antipyretic (reduces fever)[11, 17]

Antipyretic (fever)

Antiviral[1, 5, 8, 10, 11]

Antimicrobial and antiviral

Immunomodulator / immune support[10, 11]

Immunostimulant / immune support

Anti-inflammatory[12]

Anti-inflammatory for lung inflammation (traditional)

Diaphoretic[9, 10, 11, 12]

Diaphoretic - promotes sweating to support feverish illness

Expectorant[9, 10, 11, 12]

Traditional expectorant - helps clear phlegm in chest conditions, bronchitis and pleurisy

Traditional & Indicated Uses

Arthritis / joint pain[10, 11]Moderate · 5/10

inferred from anti-inflammatory action

Evidence: 5
Label: Arthritis / joint pain
Cancer (anticancer research)[14, 15, 16]Traditional · 2/10

Andrographolide (from Andrographis paniculata) acts as a chemopreventive and antitumour agent against breast, lung, colorectal, cervical, prostate and hepatocellular cancers and leukaemia, inducing apoptosis and inhibiting NF-kappaB and PI3K/AKT signalling (preclinical).

Evidence: 2
Label: Cancer (anticancer research)
Cold & flu[10, 12, 17]Good · 8/10

Symptomatic relief of the common cold and acute upper respiratory tract infection (reduces symptom severity and duration)

Evidence: 8
Label: Cold & flu
Fever[11, 17]Traditional · 2/10

Antipyretic (fever)

Evidence: 2
Label: Fever
Immune support[10, 11]Moderate · 5/10

Immunostimulant / immune support

Evidence: 5
Label: Immune support
Infection (general)[10, 12, 17]Good · 8/10

Symptomatic relief of the common cold and acute upper respiratory tract infection (reduces symptom severity and duration)

Evidence: 8
Label: Infection (general)
Inflammation (general)[10, 11]Moderate · 5/10

inferred from anti-inflammatory action

Evidence: 5
Label: Inflammation (general)
Skin irritation[10, 11]Moderate · 5/10

inferred from anti-inflammatory action

Evidence: 5
Label: Skin irritation
Sore throat[12, 17]Good · 7/10
Evidence: 7
Label: Sore throat
Wounds[10, 11]Moderate · 5/10

inferred from antimicrobial action

Evidence: 5
Label: Wounds
Arthritis / joint pain[12]Traditional · 1/10

inferred from anti-inflammatory action

Evidence: 1
Label: Arthritis / joint pain
Bronchitis[10, 11, 12]Traditional · 1/10

Traditional expectorant - helps clear phlegm in chest conditions, bronchitis and pleurisy

Evidence: 1
Label: Bronchitis
Cold & flu[11, 12]Traditional · 1/10

inferred from diaphoretic action

Evidence: 1
Label: Cold & flu
Cough[11, 12]Traditional · 1/10

inferred from expectorant action

Evidence: 1
Label: Cough
Fever[11, 12]Traditional · 1/10

inferred from diaphoretic action

Evidence: 1
Label: Fever
Inflammation (general)[12]Traditional · 1/10

Anti-inflammatory for lung inflammation (traditional)

Evidence: 1
Label: Inflammation (general)
Respiratory support[9, 10, 11, 12]Traditional · 1/10

inferred from expectorant action

Evidence: 1
Label: Respiratory support
Skin irritation[7, 12]Traditional · 2/10

inferred from anti-inflammatory action

Evidence: 2
Label: Skin irritation

Safety, Cautions & Contraindications

Safety note[10, 17]Caution

Avoid in pregnancy and when trying to conceive: high doses have shown reproductive toxicity in animals and the herb has a traditional reputation as an abortifacient.

Safety note[10]Caution

High doses have caused nephrotoxicity and reproductive toxicity in studies; use standardized products at recommended doses and avoid prolonged high-dose use.

Safety note[10, 17]Caution

May lower blood pressure and blood sugar and may interact with anticoagulant/antiplatelet, antihypertensive and immunosuppressant medicines; allergic reactions can occur.

Safety note[8, 11, 12]Caution

Contains cardiac glycosides: do NOT use in pregnancy, breastfeeding or infancy, in anyone with a heart condition, or alongside cardiac glycoside medicines (e.g. digoxin). The plant's cardenolide-rich latex is directly toxic - a documented case caused corneal injury through Na/K-ATPase inhibition.

Safety note[12]Info

Large doses are emetic and purgative (cause vomiting and diarrhoea). There is very little modern safety or efficacy data, so use only under the guidance of a qualified practitioner.

External Ids

Gbif: 3173178
Powo: urn:lsid:ipni.org:names:45226-1
Wikidata: Q1551608
Gbif: 3170305
Wikidata: Q311131

Botanical Description

Erect, branching annual herb with a slender, quadrangular (square-sectioned), dark green stem. The leaves are opposite, lance-shaped and glabrous, with a short stalk. Small, two-lipped, white flowers with purple-pink markings are borne in loose, spreading axillary and terminal racemes. The whole plant, and especially the leaves, is intensely and characteristically bitter.[11]

Height: 30-110 cm
Habit: Erect, branching annual herb
Leaves: Opposite, lance-shaped, glabrous, short-stalked
Flowers: Small, two-lipped, white flowers marked with purple-pink, in loose spreading racemes
Stem: Slender, quadrangular (square in cross-section), dark green, branching
Root: Shallow, fibrous root system
Fruit: Small, elastically dehiscent capsule
Flowering Period: September-December (varies by climate)

Erect perennial herb with hairy, unbranched stems and narrow, lance-shaped, alternate leaves (unlike most milkweeds, its sap is clear rather than milky). Vivid orange-red flowers are borne in showy, flat-topped umbel-like clusters at the stem tips, making it a prized butterfly and pollinator plant. The stout, fibrous, branching root is the medicinal part.[11]

Height: 30-90 cm
Habit: Erect, hairy perennial herb
Leaves: Narrow, lance-shaped, alternate
Flowers: Vivid orange-red flowers in showy, flat-topped umbel-like clusters
Stem: Erect, hairy, unbranched, exuding clear (not milky) sap when cut
Root: Stout, fibrous, branching taproot
Fruit: Spindle-shaped seed pod (follicle) releasing silky-tufted seeds
Flowering Period: June-September

Habitat

Native to India and Sri Lanka and widely distributed through South and Southeast Asia, growing wild in plains, hillsides, roadsides and cultivated fields; also grown commercially as a medicinal crop.[11]

Native to dry prairies, open fields, roadsides and sandy or rocky open ground across most of eastern and central North America.[11]

Harvesting

The aerial parts (leaves and tender stems) are cut just before or at the onset of flowering, when andrographolide content is typically highest, and dried in shade to preserve the bitter diterpenoid lactones.[11]

Parts: Aerial parts (leaves and herb)
Season: Before to early flowering

The root is dug in autumn after the plant has finished flowering and seeding, then cleaned and dried; given its cardiac glycoside content and near-absence of modern safety data, harvesting and use should only be undertaken with expert guidance.[11]

Parts: Root
Season: Autumn

Traditional Uses

Andrographis, the 'king of bitters', is a cornerstone bitter tonic of Ayurvedic and traditional Chinese medicine (Chuan xin lian), used for fevers, colds, sore throat, infections and liver complaints. This traditional reputation for treating the common cold and upper respiratory infections is now supported by clinical trials of standardised extracts.[10, 12]

Pleurisy root has a Native American and Eclectic-medicine reputation, reflected in its name, as an expectorant and diaphoretic for chest complaints, bronchitis and pleurisy, used to promote sweating during feverish illness and help clear phlegm.[11, 12]

Preparations

Infusion/decoction[11]

Dried aerial parts infused or lightly decocted in hot water as a very bitter traditional fever and cold remedy.

Standardised extract[10, 12]

Extract standardised to andrographolide content, taken as tablets or capsules; the form used in most clinical trials for cold/URTI symptom relief.

Decoction[11]

Dried root simmered in water as a traditional expectorant and diaphoretic remedy; given its cardiac glycoside content, only under qualified practitioner guidance.

Dosage

Standardised extract[10, 12]

Clinical trials for upper respiratory infection commonly use extracts standardised to around 60-120 mg andrographolide daily, in divided doses, for up to 5-7 days. Educational reference only, not a prescription.

Dried herb[13]

The WHO monograph on Herba Andrographidis gives, by indication - for the common cold, 1.5-3.0 g of the powdered crude drug three times daily, after meals and at bedtime; for pyrexia, a decoction from 3 g of the crude drug twice daily; for diarrhoea, a decoction from 3-9 g as a single dose as needed, or two 500 mg tablets four times daily. Note that the EMA HMPC assessed this herb and issued a public statement rather than a monograph, so there is no EU posology. Educational reference only, not a prescription.

All preparations[12]

Because the root contains cardiac glycosides and modern safety/efficacy data are very limited, no general dose is given here; use only under the guidance of a qualified practitioner, and never in pregnancy, breastfeeding, infancy, or with a heart condition or cardiac glycoside medicines. Educational reference only, not a prescription.

References

REF-1615, REF-1616, REF-1617, REF-1618, REF-1619, REF-1620, REF-1621, REF-1622, REF-1623
REF-0734, REF-0738, REF-0735, REF-1944, REF-1945, REF-1946, REF-1947, REF-0626, REF-1948, REF-1949

Lookalikes Review

Outcome: none-known
Reviewed By: Omnia Sana (owner-authorized)
Reviewed Date: 2026-07-07
Outcome: has-lookalikes
Reviewed By: Omnia Sana (owner-authorized)
Reviewed Date: 2026-07-07

Dangerous Lookalikes

Not documented

Safety note[13, 14]Dangerous
Dangerous Plant: apocynum-cannabinum
Confused Part: Young shoots (and the root) gathered from the wild; toxic dogbane sends up very similar shoots in the same habitat.
Confusion Context: Butterfly weed / pleurisy root (Asclepias tuberosa) is a milkweed whose young shoots and root have been used. Its main dangerous look-alike is dogbane (Apocynum cannabinum): at the shoot stage the two are easily confused and grow in similar places. Dogbane is a high-severity poison - its milky sap contains cardiac glycosides, all parts are toxic to humans, and poisoning can cause vomiting, weakness and cardiac arrest, while the sap blisters skin. Because the young shoots look alike, the bitterness test below matters.
Distinguishing Features: Taste/bitterness (decisive): dogbane is horribly, intensely bitter - an immediate warning to spit it out; edible milkweed shoots are not. Never swallow a bitter 'milkweed' shoot., Growth habit: dogbane shoots are thinner and firmer and branch early; milkweeds do not branch at the shoot stage. An early-branching, thin, firm shoot is likely dogbane., General: both milkweeds and dogbane have milky sap, so sap alone does not distinguish them - rely on bitterness and branching, and confirm the species before eating.
Key Test: Taste a tiny piece and check the branching (then spit it out). An intensely bitter shoot, or one that is thin, firm and branches early, is dogbane - toxic, do not eat. Milky sap alone does not prove it is safe; if in any doubt, discard it.
Reviewed By: Omnia Sana (owner-authorized)
Reviewed Date: 2026-07-07

References & Sources

  1. Okonogi, R. and others (2023) 'Efficacy of Andrographis paniculata spray in acute pharyngitis: A randomized controlled trial', Drug Discoveries & Therapeutics, 17(5), pp. 315-321. doi:10.5582/ddt.2023.01053 Randomized trial
    https://doi.org/10.5582/ddt.2023.01053
  2. Hossain, S., Urbi, Z., Karuniawati, H., Mohiuddin, R.B. and others (2018) 'Overview of pharmacological activities of Andrographis paniculata and its major compound andrographolide', Critical Reviews in Food Science and Nutrition, 61(10), pp. 1635-1652. doi:10.1080/10408398.2018.1501657 Meta-analysis / review
    https://doi.org/10.1080/10408398.2018.1501657
  3. Worakunphanich, W. and others (2021) 'Andrographis paniculata Formulations: Impact on Diterpene Lactone Oral Bioavailability', European Journal of Drug Metabolism and Pharmacokinetics, 46(5), pp. 565-581. doi:10.1007/s13318-021-00736-7 Meta-analysis / review
    https://doi.org/10.1007/s13318-021-00736-7
  4. Worakunphanich, W., Thavorncharoensap, M., Youngkong, S., Thakkinstian, A. and Chaikledkaew, U (2021) 'Safety of Andrographis paniculata: A systematic review and meta-analysis', Pharmacoepidemiology and Drug Safety, 30(6), pp. 727-739. doi:10.1002/pds.5190 Meta-analysis / review
    https://doi.org/10.1002/pds.5190
  5. Kumar, S., Singh, B. and Bajpai, V (2021) 'Andrographis paniculata (Burm.f.) Nees and its major constituent andrographolide as potential antiviral agents', Journal of Ethnopharmacology, 274, pp. 113954. doi:10.1016/j.jep.2021.113954 Meta-analysis / review
    https://doi.org/10.1016/j.jep.2021.113954
  6. Barbosa, F.L. and others (2021) 'Andrographis paniculata (Burm. f.) Wall. ex Nees: An Updated Review of Phytochemistry, Antimicrobial Pharmacology, and Clinical Safety and Efficacy', Life, 11(4), pp. 348. doi:10.3390/life11040348 Meta-analysis / review
    https://doi.org/10.3390/life11040348
  7. Singh, P. and others (2022) 'Andrographis paniculata mitigates first-line anti-tubercular drugs-induced nephrotoxicity in Wistar rats', Biomarkers, 27(4), pp. 385-394. doi:10.1080/1354750X.2022.2043444 Preclinical
    https://doi.org/10.1080/1354750X.2022.2043444
  8. Coon, J.T. and Ernst, E (2004) 'Andrographis paniculata in the symptomatic treatment of uncomplicated upper respiratory tract infection: systematic review of randomized controlled trials', Journal of Clinical Pharmacy and Therapeutics, 29(1), pp. 37-45. doi:10.1046/j.1365-2710.2003.00534.x Meta-analysis / review
    https://doi.org/10.1046/j.1365-2710.2003.00534.x
  9. Rondee, N. and others (2023) 'The Effects of Andrographis paniculata (Burm.F.) Wall. Ex Nees and Andrographolide on Neuroinflammation in the Treatment of Neurodegenerative Diseases', Nutrients, 15(15), pp. 3428. doi:10.3390/nu15153428 Meta-analysis / review
    https://doi.org/10.3390/nu15153428
  10. Zeng, B., Wei, A., Zhou, Q., Yuan, M., Lei, K., Liu, Y., Song, J., Guo, L. and Ye, Q (2021) 'Andrographolide: A review of its pharmacology, pharmacokinetics, toxicity and clinical trials and pharmaceutical researches', Phytotherapy Research. doi:10.1002/ptr.7324 Randomized trial
    https://doi.org/10.1002/ptr.7324
  11. Gonde, D.P., Bhole, B.K. and Kakad, K.S (2023) 'Andrographolide, diterpenoid constituent of Andrographis paniculata: Review on botany, phytochemistry, molecular docking analysis, and pharmacology', Annales Pharmaceutiques Francaises. doi:10.1016/j.pharma.2023.10.001 Preclinical
    https://doi.org/10.1016/j.pharma.2023.10.001
  12. Hu, X.Y., Wu, R.H., Logue, M., Blondel, C., Lai, L.Y.W., Stuart, B., Flower, A., Fei, Y.T., Moore, M., Shepherd, J., Liu, J.P. and Lewith, G (2017) 'Andrographis paniculata (Chuan Xin Lian) for symptomatic relief of acute respiratory tract infections in adults and children: A systematic review and meta-analysis', PLoS ONE. doi:10.1371/journal.pone.0181780 Meta-analysis / review
    https://doi.org/10.1371/journal.pone.0181780
  13. World Health Organization (2002) 'Herba Andrographidis'. Available at: https://iris.who.int/items/6418d8af-5200-4e6b-9bf5-004f3aa62a37 Traditional / reference
    https://iris.who.int/items/6418d8af-5200-4e6b-9bf5-004f3aa62a37
  14. Tundis, R. and Patra, J.K. and Bonesi, M. and Das, S. and Nath, R. and Das Talukdar, A. and Das, G. and Loizzo, M.R (2023) 'Anti-Cancer Agent: The Labdane Diterpenoid-Andrographolide', Plants, 12(10), pp. 1969. doi:10.3390/plants12101969 Preclinical
    https://doi.org/10.3390/plants12101969
  15. Mishra, S.K. and Tripathi, S. and Shukla, A. and Oh, S.H. and Kim, H.M (2015) 'Andrographolide and analogues in cancer prevention', Frontiers in Bioscience (Elite Edition), 7(2), pp. 255-266. doi:10.2741/E732 Preclinical
    https://doi.org/10.2741/E732
  16. Paul, S. and Roy, D. and Pati, S. and Sa, G (2021) 'The Adroitness of Andrographolide as a Natural Weapon Against Colorectal Cancer', Frontiers in Pharmacology, 12, pp. 731492. doi:10.3389/fphar.2021.731492 Preclinical
    https://doi.org/10.3389/fphar.2021.731492
  17. Memorial Sloan Kettering Cancer Center (n.d.) 'Andrographis (About Herbs)'. Available at: https://www.mskcc.org/cancer-care/integrative-medicine/herbs/andrographis Traditional / reference
    https://www.mskcc.org/cancer-care/integrative-medicine/herbs/andrographis
  1. Warashina, T. and Miyase, T (2017) 'New 8,12;8,20-diepoxy-8,14-secopregnane hexa- and hepta-glycosides from the roots of Asclepias tuberosa', Journal of Natural Medicines, 72(1), pp. 347-356. doi:10.1007/s11418-017-1155-9 Preclinical
    https://doi.org/10.1007/s11418-017-1155-9
  2. Abe, F. and Yamauchi, T (2000) 'An androstane bioside and 3'-thiazolidinone derivatives of doubly-linked cardenolide glycosides from the roots of Asclepias tuberosa', Chemical & Pharmaceutical Bulletin, 48(7), pp. 991-993. doi:10.1248/cpb.48.991 Preclinical
    https://doi.org/10.1248/cpb.48.991
  3. Lockwood, T.L (1848) 'Asclepias Tuberosa, Butterfly-Weed, Milk-Weed, Pleurisy Root, White Root', The Medical Examiner (Philadelphia), 4(42), pp. 367-368. Available at: https://pubmed.ncbi.nlm.nih.gov/38120955/ Traditional / reference
    https://pubmed.ncbi.nlm.nih.gov/38120955/
  4. Abe, F. and Yamauchi, T (2000) 'Pregnane glycosides from the roots of Asclepias tuberosa', Chemical & Pharmaceutical Bulletin, 48(7), pp. 1017-1022. doi:10.1248/cpb.48.1017 Preclinical
    https://doi.org/10.1248/cpb.48.1017
  5. Warashina, T. and Noro, T (2009) '8,14-Secopregnane glycosides from the aerial parts of Asclepias tuberosa', Phytochemistry, 70(10), pp. 1294-1304. doi:10.1016/j.phytochem.2009.07.033 Preclinical
    https://doi.org/10.1016/j.phytochem.2009.07.033
  6. Warashina, T. and Noro, T (2010) '8,12;8,20-Diepoxy-8,14-secopregnane glycosides from the aerial parts of Asclepias tuberosa', Chemical & Pharmaceutical Bulletin, 58(2), pp. 172-179. doi:10.1248/cpb.58.172 Preclinical
    https://doi.org/10.1248/cpb.58.172
  7. Warashina, T., Umehara, K., Miyase, T. and Noro, T (2011) '8,12;8,20-diepoxy-8,14-secopregnane glycosides from roots of Asclepias tuberosa and their effect on proliferation of human skin fibroblasts', Phytochemistry, 72(14-15), pp. 1865-1875. doi:10.1016/j.phytochem.2011.05.012 Preclinical
    https://doi.org/10.1016/j.phytochem.2011.05.012
  8. Mikkelsen, L.H., Hamoudi, H., Gul, C.A. and Heegaard, S (2017) 'Corneal Toxicity Following Exposure to Asclepias Tuberosa', The Open Ophthalmology Journal, pp. 1--4. doi:10.2174/1874364101711010001 Preclinical
    https://doi.org/10.2174/1874364101711010001
  9. Lockwood, T.L (1848) 'Asclepias Tuberosa, Butterfly-Weed, Milk-Weed, Pleurisy Root, White Root', Medical Examiner (Philadelphia), 4(42), pp. 367-368. Traditional / reference
    https://scholar.google.com/scholar?q=Asclepias%20Tuberosa%2C%20Butterfly-Weed%2C%20Milk-Weed%2C%20Pleurisy%20Root%2C%20White%20Root
  10. Lockwood, T.T (1848) 'Asclepias Tuberosa, Butter-Fly-Weed, Milk Weed, Pleurisy Root, White Root', Buffalo Medical Journal and Monthly Review, 3(10), pp. 600-602. Traditional / reference
    https://scholar.google.com/scholar?q=Asclepias%20Tuberosa%2C%20Butter-Fly-Weed%2C%20Milk%20Weed%2C%20Pleurisy%20Root%2C%20White%20Root
  11. The Naturopathic Herbalist (n.d.) 'Asclepias tuberosa'. Available at: https://thenaturopathicherbalist.com/2015/09/06/asclepius-tuberosa/ Traditional / reference
    https://thenaturopathicherbalist.com/2015/09/06/asclepius-tuberosa/
  12. Herbs2000 (n.d.) 'Pleurisy Root (Asclepias tuberosa)'. Available at: https://www.herbs2000.com/herbs/herbs_pleurisy_root.htm Traditional / reference
    https://www.herbs2000.com/herbs/herbs_pleurisy_root.htm
  13. Forager Chef 'Foraging and Cooking Milkweed'. Available at: https://foragerchef.com/guide-to-milkweed/ Traditional / reference
    https://foragerchef.com/guide-to-milkweed/
  14. North Carolina Extension Gardener Plant Toolbox 'Apocynum cannabinum (Dogbane)'. Available at: https://plants.ces.ncsu.edu/plants/apocynum-cannabinum/ Traditional / reference
    https://plants.ces.ncsu.edu/plants/apocynum-cannabinum/

Generated automatically from the Omnia Sana plant database and its cited sources. For educational purposes only — not medical advice. Always consult a qualified practitioner before using medicinal plants.