Plant Profile

Pleurisy Root

Compiled by the Omnia Sana editorial team from the plant database ·Last updated August 14, 2026

Asclepias tuberosa

Family: Apocynaceae · Parts used: Root · Also known as: Butterfly weed, Butterfly milkweed, Orange milkweed

The complete database record: 2 documented constituents, 3 pharmacological actions, 8 traditional / indicated uses, with 14 cited sources.

Botanical Description

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.^[10]

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 & Distribution

Native to dry prairies, open fields, roadsides and sandy or rocky open ground across most of eastern and central North America.^[10]

Harvesting

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.^[10]

Parts: Root

Season: Autumn

Key Constituents

Cardiac glycosides (cardenolides such as asclepin, calactin and calotropin)^{[10, 11]}

Heart-active compounds that make dosing and safety critical.

Glycosides

Flavonoids and amino acids^[11]

Supporting constituents of the root.

Flavonoids

Pharmacological Actions

Anti-inflammatory^[11]

Anti-inflammatory for lung inflammation (traditional)

Diaphoretic^{[9, 10, 11]}

Diaphoretic - promotes sweating to support feverish illness

Expectorant^{[9, 10, 11]}

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

Traditional & Indicated Uses

Arthritis / joint pain^[11]Preliminary · 1/10

inferred from anti-inflammatory action

Evidence: 1

Label: Arthritis / joint pain

more plants for arthritis / joint pain →detailed sources →

Bronchitis^{[9, 10, 11]}Preliminary · 1/10

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

Evidence: 1

Label: Bronchitis

more plants for bronchitis →detailed sources →

Cold & flu^{[10, 11]}Preliminary · 1/10

inferred from diaphoretic action

Evidence: 1

Label: Cold & flu

more plants for cold & flu →detailed sources →

Cough^{[10, 11]}Preliminary · 1/10

inferred from expectorant action

Evidence: 1

Label: Cough

more plants for cough →detailed sources →

Fever^{[10, 11]}Preliminary · 1/10

inferred from diaphoretic action

Evidence: 1

Label: Fever

more plants for fever →detailed sources →

Inflammation (general)^[11]Preliminary · 1/10

Anti-inflammatory for lung inflammation (traditional)

Evidence: 1

Label: Inflammation (general)

more plants for inflammation (general) →detailed sources →

Respiratory support^{[9, 10, 11]}Preliminary · 1/10

inferred from expectorant action

Evidence: 1

Label: Respiratory support

more plants for respiratory support →detailed sources →

Skin irritation^{[7, 11]}Preliminary · 2/10

inferred from anti-inflammatory action

Evidence: 2

Label: Skin irritation

more plants for skin irritation →detailed sources →

Traditional Use & History

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.^{[10, 11]}

Preparations

Decoction^[10]

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

Dosage

All preparations^[11]

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.

Safety, Cautions & Contraindications

Safety note^{[8, 10, 11]}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^[11]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.

Dangerous Lookalikes

Apocynum Cannabinum^{[13, 14]}Dangerous

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

Harvest Readiness

^[12]

Part: root

Signals: Dig the root in autumn, after the aerial parts die back; it can be used fresh or dried., SAFETY: pleurisy-root is confusable with the toxic hemp dogbane (Apocynum cannabinum), especially at the root. Confirm identity before digging - see this plant's Dangerous Lookalikes.

Basis: traditional

Source Quote: The root is harvested in the autumn and can be used fresh or dried.

Species Confirmed: 1

Notes: Useful Temperate Plants (REF-3211) for Asclepias tuberosa. Single source -> provisional.

External Identifiers

GBIF ›Wikidata ›

References & Sources

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
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
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/
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
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
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
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
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
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
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/
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
Fern, Ken 'Asclepias tuberosa (Pleurisy Root) — Useful Temperate Plants'. Available at: https://temperate.theferns.info/plant/Asclepias+tuberosa Traditional / reference
https://temperate.theferns.info/plant/Asclepias+tuberosa
Forager Chef 'Foraging and Cooking Milkweed'. Available at: https://foragerchef.com/guide-to-milkweed/ Traditional / reference
https://foragerchef.com/guide-to-milkweed/
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/

Selected studies & references

PreclinicalCorneal Toxicity Following Exposure to Asclepias Tuberosa source↗ (2017)

PreclinicalNew 8,12;8,20-diepoxy-8,14-secopregnane hexa- and hepta-glycosides from the roots of Asclepias tuberosa source↗ (2017)

Preclinical8,12;8,20-diepoxy-8,14-secopregnane glycosides from roots of Asclepias tuberosa and their effect on proliferation of human skin fibroblasts source↗ (2011)

Preclinical8,12;8,20-Diepoxy-8,14-secopregnane glycosides from the aerial parts of Asclepias tuberosa source↗ (2010)

Preclinical8,14-Secopregnane glycosides from the aerial parts of Asclepias tuberosa source↗ (2009)

PreclinicalAn androstane bioside and 3'-thiazolidinone derivatives of doubly-linked cardenolide glycosides from the roots of Asclepias tuberosa source↗ (2000)

PreclinicalPregnane glycosides from the roots of Asclepias tuberosa source↗ (2000)

TraditionalAsclepias Tuberosa, Butterfly-Weed, Milk-Weed, Pleurisy Root, White Root source↗ (1848)

All 11 studies in the Knowledge Finder →

Educational use only. This profile summarises traditional and scientific sources for reference. It is not medical advice and not a substitute for a qualified practitioner. Some plants carry safety cautions and drug interactions - always check before use.
This profile is assembled automatically from the Omnia Sana plant database, which we curate by hand. How this site is built.

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