Da Feng Zi
StarHydnocarpus anthelminthicus Pierre ex Laness.
Traditionally used for
- Skin
Cautions & contraindications
- Pregnancy
- Kidney conditions
- Toxic — professional use only
☯ TCM Properties
Expels Wind, d ries Dampness, a ttacks toxicity and k ills parasites
Traditional Chinese Uses
Da Feng Zi (Semen Hydnocarpi) is the ripe seed of the chaulmoogra tree, Hydnocarpus anthelminthicus. Pungent and hot and classed among the external-application substances, it expels Wind, dries Dampness, attacks toxicity, and kills parasites. It is famous historically as a leprosy remedy - used in China from around the 14th century - and is applied to scabies, tinea (ringworm), stubborn tinea-type sores, and rosacea, usually as an oil, ointment, or ground-seed paste.
Da Feng Zi is considered strongly toxic and is essentially for external use. Internal ingestion can cause serious poisoning - vomiting, kidney and vision damage, and neurological effects - so oral use is avoided or, historically, given only in tiny, carefully controlled amounts. It is contraindicated in pregnancy and in Yin-deficient Heat patterns.
Western Herbalism Properties
Relationships
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Botanical Description
Da Feng Zi is the ripe seed of Hydnocarpus anthelminthica Pierre ex Laness. (Achariaceae, formerly Flacourtiaceae), the chaulmoogra tree, a medium-sized evergreen tree 6 to 20 m tall native to Indochina, Thailand, Myanmar, and southern China. Leaves are alternate, elliptic to oblong-lanceolate, leathery, and entire; dioecious axillary clusters of small pink-white flowers give rise to globose woody capsules 6 to 8 cm across containing 30 to 50 angular brown seeds. WARNING: The seed and its fixed oil, chaulmoogra oil, are toxic gastrointestinal and dermal irritants and were largely abandoned with the advent of dapsone and multidrug therapy. The oil was historically the principal worldwide treatment for leprosy from the late nineteenth century into the mid twentieth century, and the seed is also documented in classical Chinese sources. In traditional Chinese medicine the seed is acrid, hot, and toxic, entering the Liver, Spleen, and Kidney channels; it kills parasites, dries damp, and resolves toxicity, used externally for leprosy, syphilitic sores, scabies, ringworm, and stubborn skin disease.
Active Constituents
Hydnocarpic acid
Cyclopentenyl fatty acid (11-(2-cyclopenten-1-yl)undecanoic acid)Concentration: Reported at roughly 35% of the fatty acids of chaulmoogra oil; note that published analyses are frequently of oil from Hydnocarpus wightianus rather than H. anthelminthicus
The principal cyclopentenyl fatty acid of chaulmoogra oil and, with chaulmoogric acid, the compound to which the oil's historical antileprotic action was attributed. The terminal cyclopentenyl ring is a rare structural feature that makes these acids poor substrates for normal fatty acid beta-oxidation, and this interference with mycobacterial lipid metabolism is the classical explanation for their selective bactericidal effect on Mycobacterium leprae. The sodium salt was marketed as Alepol in 1927 to make the drug tolerable. Historical practice is important context, not a current recommendation: chaulmoogra was superseded by the sulfones from the 1940s and has no place in modern leprosy treatment.
Chaulmoogric acid
Cyclopentenyl fatty acid (13-(2-cyclopenten-1-yl)tridecanoic acid)Concentration: Reported at roughly 22% of the fatty acids of chaulmoogra oil, with the same caveat about source species
The two-carbon homologue of hydnocarpic acid and the compound that gave the oil its name. Isolated by Power and colleagues at the Wellcome laboratories in the early 1900s from both H. wightianus and H. anthelminthicus. It shares hydnocarpic acid's activity against Mycobacterium leprae and its poor oral tolerability: taken by mouth the oil is strongly nauseating and was frequently abandoned by patients, while intramuscular injection was intensely painful, which is why benzocaine-containing formulations were developed.
Gorlic acid and lower cyclic homologues
Cyclopentenyl fatty acidsConcentration: Minor components of the seed oil
Structurally related cyclopentenyl acids present alongside the two principal ones. They share the same unusual ring system and are assumed to contribute to the oil's activity, but they have not been separately characterised pharmacologically to a clinically useful degree.
Conventional fatty acids (palmitic, stearic, oleic, linoleic, myristic and palmitoleic acids)
Straight-chain saturated and unsaturated fatty acidsConcentration: Make up the remainder of the seed oil alongside the cyclopentenyl acids
The ordinary fatty acid fraction of the oil, without specific antimycobacterial activity. They determine the oil's physical properties as a vehicle and account for its emollient behaviour in the topical dermatological uses that survive in Chinese and Ayurvedic practice.
Flavonolignans (hydnocarpin, isohydnocarpin, neohydnocarpin, hydnowightin)
FlavonolignansConcentration: Minor seed constituents; the reported isolations and pharmacology are from Hydnocarpus wightianus rather than from H. anthelminthicus
A group of flavonolignans reported from Hydnocarpus seeds, of which hydnocarpin is the best known. Sharma and Hall reported hypolipidaemic, anti-inflammatory and antineoplastic activity together with cytotoxicity for flavonolignans isolated from Hydnocarpus wightiana seeds. This work is on a different species from the one this record covers and has not been reproduced clinically in any species, so it should be read as chemistry of the genus rather than as pharmacology of Da Feng Zi.
⚠ Drug Interactions
WHO multidrug therapy for leprosy (dapsone, rifampicin, clofazimine)
This is the clinically important interaction and it is one of substitution rather than pharmacology. Chaulmoogra oil was the only treatment for leprosy for roughly a century and was displaced by the sulfones from the 1940s because they are dramatically more effective. Leprosy is now curable with WHO multidrug therapy, which is supplied free worldwide, while the nerve damage the disease causes is not reversible once established. Using Da Feng Zi as a treatment for leprosy, or allowing its use to delay presentation, converts a curable infection into permanent disability. There is no published evidence that chaulmoogra adds anything to multidrug therapy, and no pharmacokinetic interaction data exist to guide co-administration.
Clinical note: Da Feng Zi must not be offered as a treatment for leprosy. Any patient with anaesthetic skin patches, thickened peripheral nerves or suspected leprosy needs urgent referral for WHO multidrug therapy. The herb's surviving role is topical, in chronic scaly and parasitic skin conditions, and even there it is a historical rather than an evidence-based choice.
Hydnocarpus wightianus (H. pentandrus) and H. kurzii, substituted as chaulmoogra oil
Commercial chaulmoogra oil is not a single-species product. Hydnocarpus wightianus is the major commercial source, with H. kurzii and H. anthelminthicus also used, and most of the published phytochemical and pharmacological analyses attributed to chaulmoogra oil were performed on H. wightianus material. The species differ in the proportions of hydnocarpic, chaulmoogric and gorlic acids, so a monograph built on the literature is describing a genus-level composite rather than H. anthelminthicus specifically. Ayurvedic and Chinese supply chains draw on different species, and the label rarely distinguishes them.
Clinical note: Treat published potency and composition figures for chaulmoogra oil as approximate for this species. Where species identity matters, request botanical authentication rather than relying on the trade name.
NSAIDs, corticosteroids and other gastric irritants
The dose-limiting problem with oral chaulmoogra oil throughout its therapeutic history was severe nausea and gastric intolerance, severe enough that patients described the treatment as worse than the disease and abandoned it. Any co-administered gastric irritant would be expected to compound this. No formal interaction study exists; this is an inference from the drug's well-documented tolerability profile.
Clinical note: Oral use of the seed or oil is not recommended. If any oral preparation is used, avoid concurrent NSAIDs and warn about nausea, which is the near-universal effect rather than an idiosyncratic one.
Dosage
| Form | Amount | Frequency | Duration | Population | Notes |
|---|---|---|---|---|---|
| topical | Appropriate amount | — | — | — | No Chinese Pharmacopoeia 2025 monograph found for this drug, so no pharmacopoeial dose is given here. *Hydnocarpus anthelminthicus*, chaulmoogra — used chiefly EXTERNALLY, as an oil or paste, for chronic skin disease, tinea and historically for leprosy. Internal use causes nausea, vomiting and abdominal pain and is avoided; no pharmacopoeial internal dose exists. The previous value was generic filler generated from tcm_category and was cleared; it has not been replaced with an estimate. |
Evidence Tier
Moderate evidence · 3 studiesRecorded studies by study design, strongest design at the top. This is a study-design tier only, not a GRADE rating: it does not weigh risk of bias, consistency or precision.
Systematic review / meta-analysis
0
Randomized controlled trial
0
Other clinical trial
0
Observational / case report
2
0 verified · 2 unverified
In vitro / animal
1
0 verified · 1 unverified
Other / unclassified
0
Verified: design read from PubMed for a DOI that resolves to the cited paper Unverified: taken from the study's recorded description
Clinical Studies
Chaulmoogra Oil in the Treatment of Leprosy
A contemporary clinical account from the pre-sulfone era of chaulmoogra oil used to treat leprosy, describing regimens, routes of administration and outcomes as they were understood at the time. Included as the primary historical record of how this drug was actually used, not as evidence supporting current use.
Benzocaine-Chaulmoogra Oil in the Treatment of Leprosy: Preliminary Note on the Use of an Oil-Soluble Analgesic Which Renders Intramuscular Injections of Chaulmoogra Chaulmoogra Oil Painless
Report from the United States leprosy service on adding an oil-soluble local anaesthetic to injected chaulmoogra oil to make intramuscular administration tolerable. It documents directly how painful the injections were, which together with the nausea of the oral route was the main reason the treatment failed in practice long before the sulfones displaced it.
Hypolipidemic, Anti-Inflammatory, and Antineoplastic Activity and Cytotoxicity of Flavonolignans Isolated from Hydnocarpus wightiana Seeds
Flavonolignans isolated from Hydnocarpus wightiana seeds showed hypolipidaemic, anti-inflammatory and antineoplastic activity along with cytotoxicity in laboratory models. The species studied is H. wightiana, not the H. anthelminthicus of this record, so the findings characterise the genus rather than this drug, and they have not been followed up clinically.
⚠ Safety & Contraindications
- Pregnancy
- Kidney conditions
- Toxic — professional use only
Contraindications
Due to its fierce toxicity, it is usually just for external use; if for oral use, its use should be cautious and prohibited in patients with blood heat and yin deficiency.
Source: Xi S, Gong Y. Essentials of Chinese Materia Medica and Medical Formulas. Academic Press/Elsevier, 2017, p. 409.
Historical Texts
Ben Cao Gang Mu
Ming dynastyReferences
- Sahoo Manas Ranjan; Dhanabal S.P.; Jadhav Atul N.; Reddy Vishali; Muguli Ganesh; Babu U.V.; Rangesh Paramesh. Hydnocarpus: An ethnopharmacological, phytochemical and pharmacological review . Journal of Ethnopharmacology (2014) [DOI]
- Parascandola John. Chaulmoogra Oil and the Treatment of Leprosy . Studies in the History of Modern Pharmacology and Drug Therapy (2023) [DOI]
This information is for educational purposes only and is not intended to replace professional medical advice. Always consult a qualified healthcare provider before using any herbal remedy, especially if you are pregnant, nursing, or taking medications.
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