Dragon's Blood (Croton lechleri)

Table of Contents

1. What Dragon's Blood Is
2. One Name, Several Unrelated Plants
3. Traditional Uses in the Amazon
4. What Is in the Sap
5. From Sap to a Licensed Drug: Crofelemer
6. Wounds, Insect Bites and the Skin
7. Laboratory Findings: Inflammation, Cells and Cancer Lines
8. Taspine, Mutagenicity and Safety Findings
9. Forms and Amounts Described in the Research
10. Where the Evidence Stands
11. Key Research Papers
12. Connections
13. Featured Videos

What Dragon's Blood Is

Croton lechleri Müll. Arg. is a tree of the upper Amazon basin; a 2002 chemical survey collected it from 22 sites across northern Peru and Ecuador. The material people use is the latex, often loosely called the sap or resin: a deep red liquid that flows from cuts made in the stem bark.

The latex is not a single compound. It is a mixture dominated by proanthocyanidins, the same broad family of astringent polyphenols found in grape seeds and pine bark. A 2025 review of 33 studies from the previous two decades identified proanthocyanidins as the predominant group by quantity, with smaller amounts of alkaloids, diterpenoids, plant sterols, saponins and other phenolic compounds. The one alkaloid that stands out is taspine, discussed in detail below.

The Spanish names vary by country and by writer: sangre de drago, sangre de grado, or simply sangre de dragón. All of them mean the same thing, and the same English words are used for several other plant resins, which is the subject of the next section.

One Name, Several Unrelated Plants

"Dragon's blood" is a trade name for a colour and a look, not a botanical identity. A 2008 review in the Journal of Ethnopharmacology noted that the red saps and resins sold under this name "are derived from a number of disparate taxa," and that despite wide use, little research had been done on their true source, quality control and clinical applications. A 2019 analytical chemistry paper put it more precisely: dragon's blood can come from at least four entirely different plant families.

• Croton (spurge family): the Amazonian latex on this page, plus related South American species such as Croton palanostigma.
• Dracaena (asparagus family): the dragon trees, including Dracaena cinnabari of Socotra Island in Yemen and Dracaena cochinchinensis, the source of Chinese dragon's blood.
• Daemonorops (palm family): the palm Daemonorops draco, which one pharmacopoeia treats as the only "authentic" source of dragon's blood.
• A fourth source in the pea family (Fabaceae).

These plants are not closely related and their resins are chemically different. Laboratories identify the palm resin by a red flavonoid pigment called dracorhodin and the Dracaena resins by compounds called loureirin A and B; the Croton material is a liquid latex dominated by proanthocyanidins and containing taspine. A study, a product or a safety finding about one of them tells you little about the others. Wherever possible this page and its four companion articles name the species. The full comparison is in Four Plants, One Name.

Traditional Uses in the Amazon

The research literature records a consistent set of folk uses for the Croton latex. Laboratory papers on the sap list them in their introductions, and a 2003 review gathered them in one place:

• Wounds and skin injuries. The latex is applied directly to cuts, grazes and other wounds as a "cicatrizant", an old word for something that helps a wound close and scar over. One paper also lists fractures and haemorrhoids among the external uses.
• Insect bites and stings. Applied to bites for itching, pain and swelling.
• Diarrhoea. Taken by mouth for loose and watery stools.
• Stomach and intestinal ulcers. Taken internally.
• Inflammation. Used as a general anti-inflammatory remedy.
• Viral infections and tumours. Laboratory papers note "empirical" use against cancers, meaning use based on experience rather than tested evidence.

The 2003 review concluded that laboratory and animal studies "largely support" most of these uses, including diarrhoea, wounds, stomach ulcers, herpes infection and insect bites. That is the review's judgement about preclinical findings, and readers can weigh it against how little human trial data exists. The drug that eventually emerged addressed only one of these indications, diarrhoea, and only one cause of it.

What Is in the Sap

Three findings about the latex's chemistry matter most for reading the rest of the research.

Proanthocyanidins are the bulk

Proanthocyanidins (also called condensed tannins) are chains of linked flavan-3-ol units. They bind proteins, which is why tannin-rich materials feel astringent and why they have long been used on raw tissue and for diarrhoea. The 2025 review found them to be the most abundant constituent group in Croton lechleri. Crofelemer is an oligomeric proanthocyanidin, a purified mixture of medium-length chains of this kind taken from the latex.

Taspine is the notable alkaloid

A 2002 survey analysed latex and leaf samples from 22 sites across northern Peru and Ecuador. The leaves contained up to six different alkaloids, but the latex contained only one: taspine. Its average concentration across the range was 9% of the latex by dry weight. The authors described taspine as the component earlier work had identified as responsible for the latex's wound-healing activity. They also defined three different chemical types (chemotypes) of the tree based on leaf alkaloids, which means the plant's chemistry varies with where it grows.

Composition varies

The geographic variation matters. The 2003 review pointed out that sap from one area can differ chemically from sap from another, and that any material developed for clinical use would need standardising. Even the purified drug varies between lots: a 2017 study by university and FDA scientists used crofelemer specifically as a model of a "complex mixture" drug whose lots differ because of their natural source.

From Sap to a Licensed Drug: Crofelemer

Crofelemer is the reason dragon's blood appears in mainstream medical journals. Here is the short version; the full story is in Crofelemer: From Sap to Licensed Drug.

• What it is. A purified oligomeric proanthocyanidin extracted from the stem-bark latex of Croton lechleri.
• How it works. Laboratory work at the University of California, San Francisco found that it blocks two chloride channels in the gut lining: CFTR (the channel that is faulty in cystic fibrosis) and a calcium-activated channel called TMEM16A. In secretory diarrhoea, chloride pumped into the gut pulls water with it. Blocking both channels reduces that flow.
• Where it acts. It is minimally absorbed when swallowed and acts locally inside the intestine.
• The trial. The ADVENT trial randomised 376 people with HIV on stable antiretroviral therapy who had chronic non-infectious diarrhoea. Over four weeks, 17.6% of those taking 125 mg twice daily met the response definition (two or fewer watery stools a week for at least two of the four weeks), against 8.0% on placebo.
• The approval. The US Food and Drug Administration approved it in December 2012 for the symptomatic relief of non-infectious diarrhoea in adults with HIV/AIDS on antiretroviral therapy. A 2013 review described it as the first, and at that time only, drug approved specifically for that use.

The response rates show that the benefit was real but modest: most people in both groups did not meet the response definition during the four-week controlled phase. A trial of crofelemer in diarrhoea-predominant irritable bowel syndrome did not meet its main goal. A small trial for chemotherapy-induced diarrhoea in breast cancer also missed its primary endpoint, while showing fewer moderate-to-severe episodes in the second treatment cycle.

Wounds, Insect Bites and the Skin

Skin use is the oldest and most widespread use of the latex, and it is also where the human evidence is thinnest.

A 2019 dermatology review from a US medical school searched PubMed for "Dragon's Blood" and "Croton lechleri". It found preclinical studies pointing to anti-inflammatory, antioxidant, antimicrobial, antifungal and anti-tumour properties, and clinical studies reflecting wound-healing and antiviral properties. Its overall conclusion was cautious: the plant "offers limited use in dermatology" and needs further investigation. The 2003 review reported that clinical studies of sap products had reported positive results for the symptoms of insect bites. Neither abstract describes a large, independent, placebo-controlled wound trial of the sap, and we found none in our citation pack.

The laboratory picture is more developed. In a 2003 Barcelona study, the latex inhibited both main pathways of the complement system (part of the innate immune defence) in human serum, slowed the multiplication of activated T-cells, and had a strong anti-inflammatory effect in the rat paw-swelling test when injected into the abdomen. Taspine alone could not account for these effects; the authors suggested the proanthocyanidins were also involved.

A large body of human data on "dragon's blood" for wounds does exist, but it concerns the Chinese resin Resina Draconis, not the Amazonian sap. A 2015 meta-analysis of 14 Chinese randomised trials with 618 patients found Resina Draconis associated with higher healing rates for pressure ulcers than other topical treatments (risk ratio 2.07). The authors noted the limited quality of the trials. That finding cannot be transferred to Croton lechleri. The details are in Wound Healing and Insect Bites.

Laboratory Findings: Inflammation, Cells and Cancer Lines

Most of the remaining research on Croton lechleri was done in cell cultures, test tubes and animals. None of these findings shows an effect in people.

• Cancer cell lines. In a 2012 study from Padua, the sap slowed the growth of human melanoma cells (SK23) from 1 µg/mL, with roughly ten times higher concentrations needed for two colon cancer lines. Taspine on its own inhibited the melanoma and colon lines at 0.1 µg/mL. A separate 2012 Mexican study found a methanol extract of the leaves toxic to cervical cancer (HeLa) cells and reported slower tumour growth in mice given injections. A 2024 study of twig extracts found dose-dependent toxicity to both melanoma cells and normal human skin cells, with one extract more selective for the cancer cells.
• Antioxidant and vascular effects. In 2022 the Padua group reported that the sap reduced protein glycation (the sugar damage behind "AGEs") in a test tube, lengthened the lag phase before LDL cholesterol particles began to oxidise by almost 60% at 0.8 µg/mL, and reduced reactive oxygen species in human blood-vessel cells grown in culture.
• Muscle effects in rats. In 2009 the same group found that the sap constricted rat tail arteries in a concentration-dependent way and slightly increased tension in rat stomach muscle. This is an unexpected effect for a remedy applied to bleeding wounds and swallowed for gut complaints, and its relevance to people is unknown.

Killing cancer cells in a dish is common among plant extracts and is not the same as treating cancer. The same chemistry raises safety questions, covered next.

Taspine, Mutagenicity and Safety Findings

Popular sources often describe dragon's blood as gentle. The 2003 review, for example, described the sap as having "low toxicity", and preparations used in clinical studies were reported to be well tolerated. Laboratory findings published since then are more mixed:

• Mutagenicity. A 2004 Brazilian study ran the standard Ames test (which uses Salmonella bacteria to detect DNA-damaging substances) on the latex. The sap was mutagenic in strain TA1535 when a liver-enzyme activation mix was added, and weakly mutagenic in strain TA98. It was also mutagenic in a yeast strain. The same paper found antioxidant activity in other conditions.
• Genotoxicity of a related sap. In 2013, researchers gave mice the sap of a related species, Croton palanostigma, whose main identified compound was also taspine. At all three doses tested (300, 1,000 and 2,000 mg/kg by mouth), it damaged DNA in white blood cells and liver cells, and the two higher doses caused chromosome damage in bone marrow. The authors concluded that the findings suggest caution about human use, given a possible cancer risk.
• Acute toxicity of the leaf extract. The 2012 Mexican study measured a lethal dose for half the mice (LD50) of 356 mg/kg by injection and 500 mg/kg by mouth for a methanol extract of the leaves, and described "moderate toxic effects in vivo".
• Taspine is cytotoxic. It kills or stops the growth of cells in culture at low concentrations. That is why it is studied as a possible anti-cancer lead, and it is also a reason for caution with a material containing about 9% taspine by dry weight.

The purified drug has a separate safety record. Crofelemer was generally well tolerated in its trials, it is minimally absorbed, and the US LiverTox database reports occasional enzyme elevations during therapy but no cases of clinically apparent liver injury. That record belongs to the purified proanthocyanidin, though, not to the whole latex with its taspine. There are no published human safety studies of the crude sap taken by mouth, and no pregnancy or drug-interaction data. More in Taspine, Toxicity and Safety Unknowns.

Forms and Amounts Described in the Research

Three very different things are sold or studied under this plant's name:

• The crude latex. Sold as a red liquid, traditionally applied to the skin or taken by mouth. No standardised dose has been established in clinical trials, and the taspine and proanthocyanidin content varies with where the tree grew.
• Topical sap products. Ointments and balms containing the latex, the kind of preparation the 2003 review referred to for insect bites. Their make-up and strength vary.
• Crofelemer. A prescription drug taken by mouth. The approval trial used 125 mg twice daily; the IBS trial tested 125, 250 and 500 mg twice daily, and the chemotherapy trial used 125 mg twice daily. These doses refer to the purified drug and cannot be translated into an amount of sap.

Cosmetic creams labelled "dragon's blood" are a further category. A 2020 review of Korean cosmetic ingredients listed dragon's blood among plant-derived actives. That review's summary does not say which of the several dragon's-blood plants the ingredient comes from.

Decisions about using any remedy for diarrhoea, a non-healing wound or any long-term condition belong with a clinician, particularly because a 2016 review notes that diarrhoea in people with HIV is under-reported and may have a treatable infectious or non-infectious cause.

Where the Evidence Stands

• Established: a purified proanthocyanidin from this latex, crofelemer, reduced non-infectious diarrhoea in people with HIV on antiretroviral therapy in a phase 3 placebo-controlled trial and was approved by the US FDA in December 2012. The effect was modest.
• Negative or mixed: crofelemer did not improve the main bowel endpoints in diarrhoea-predominant IBS, and missed its primary endpoint in a small chemotherapy-diarrhoea trial.
• Preclinical: anti-inflammatory, immune-modulating, antioxidant and anti-cancer-cell activity of the sap and taspine in laboratory and animal studies.
• Traditional, thinly tested in humans: topical use on wounds and insect bites. Reviews mention positive clinical reports, but no large, independent, placebo-controlled trial of the crude latex.
• Safety signals: the latex is mutagenic in bacterial and yeast tests, a related Croton sap is genotoxic in mice, and taspine is cytotoxic. Human safety data on the crude sap are absent.
• Often confused: human wound data on "dragon's blood" for pressure ulcers concern a Chinese resin from different plants.

The drug and the sap are different things. Crofelemer's approval shows that the latex contains a useful molecule. It does not show that the whole latex, with its alkaloid and variable composition, is safe or effective to take.

Key Research Papers

1. Jones K. Review of sangre de drago (Croton lechleri)--a South American tree sap in the treatment of diarrhea, inflammation, insect bites, viral infections, and wounds: traditional uses to clinical research. Journal of alternative and complementary medicine (New York, N.Y.). 2003;9(6):877-96. PubMed PMID: 14736360
2. de Albuquerque RDDG, León-Vargas FR, Carrasco-Montañez DD, et al. A Review on Phytochemistry and Recent Pharmacology of Dragon's Blood (Croton lechleri), a Multifunctional Ethnomedicinal Resource from the Amazon Forest. Planta medica. 2025;91(8):409-418. PubMed PMID: 40043740
3. Pona A, Cline A, Kolli SS, et al. Review of future insights of Dragon's Blood in dermatology. Dermatologic therapy. 2019;32(2):e12786. PubMed PMID: 30556246
4. Milanowski DJ, Winter RE, Elvin-Lewis MP, et al. Geographic distribution of three alkaloid chemotypes of Croton lechleri. Journal of natural products. 2002;65(6):814-9. PubMed PMID: 12088421
5. Risco E, Ghia F, Vila R, et al. Immunomodulatory activity and chemical characterisation of sangre de drago (dragon's blood) from Croton lechleri. Planta medica. 2003;69(9):785-94. PubMed PMID: 14598201
6. Tradtrantip L, Namkung W, Verkman AS. Crofelemer, an antisecretory antidiarrheal proanthocyanidin oligomer extracted from Croton lechleri, targets two distinct intestinal chloride channels. Molecular pharmacology. 2010;77(1):69-78. PubMed PMID: 19808995
7. Macarthur RD, Hawkins TN, Brown SJ, et al. Efficacy and safety of crofelemer for noninfectious diarrhea in HIV-seropositive individuals (ADVENT trial): a randomized, double-blind, placebo-controlled, two-stage study. HIV clinical trials. 2013;14(6):261-73. PubMed PMID: 24334179
8. Frampton JE. Crofelemer: a review of its use in the management of non-infectious diarrhoea in adult patients with HIV/AIDS on antiretroviral therapy. Drugs. 2013;73(10):1121-9. PubMed PMID: 23807722
9. Yeo QM, Crutchley R, Cottreau J, et al. Crofelemer, a novel antisecretory agent approved for the treatment of HIV-associated diarrhea. Drugs of today (Barcelona, Spain : 1998). 2013;49(4):239-52. PubMed PMID: 23616951
10. Mangel AW, Chaturvedi P. Evaluation of crofelemer in the treatment of diarrhea-predominant irritable bowel syndrome patients. Digestion. 2008;78(4):180-6. PubMed PMID: 19092244
11. Pohlmann PR, Graham D, Wu T, et al. HALT-D: a randomized open-label phase II study of crofelemer for the prevention of chemotherapy-induced diarrhea in patients with HER2-positive breast cancer receiving trastuzumab, pertuzumab, and a taxane. Breast cancer research and treatment. 2022;196(3):571-581. PubMed PMID: 36280642
12. Logan C, Beadsworth MB, Beeching NJ. HIV and diarrhoea: what is new? Current opinion in infectious diseases. 2016;29(5):486-94. PubMed PMID: 27472290
13. Xu J, Xiong T, Yang Y, et al. Resina Draconis as a topical treatment for pressure ulcers: A systematic review and meta-analysis. Wound repair and regeneration : official publication of the Wound Healing Society [and] the European Tissue Repair Society. 2015;23(4):565-74. PubMed PMID: 25968301
14. Gupta D, Bleakley B, Gupta RK. Dragon's blood: botany, chemistry and therapeutic uses. Journal of ethnopharmacology. 2008;115(3):361-80. PubMed PMID: 18060708
15. Montopoli M, Bertin R, Chen Z, et al. Croton lechleri sap and isolated alkaloid taspine exhibit inhibition against human melanoma SK23 and colon cancer HT29 cell lines. Journal of ethnopharmacology. 2012;144(3):747-53. PubMed PMID: 23123266
16. Alonso-Castro AJ, Ortiz-Sánchez E, Domínguez F, et al. Antitumor effect of Croton lechleri Mull. Arg. (Euphorbiaceae). Journal of ethnopharmacology. 2012;140(2):438-42. PubMed PMID: 22301443
17. Lopes MI, Saffi J, Echeverrigaray S, et al. Mutagenic and antioxidant activities of Croton lechleri sap in biological systems. Journal of ethnopharmacology. 2004;95(2-3):437-45. PubMed PMID: 15507372
18. Maistro EL, Ganthous G, Machado Mda S, et al. Dragon's blood Croton palanostigma induces genotoxic effects in mice. Journal of ethnopharmacology. 2013;147(2):406-11. PubMed PMID: 23528364
19. Crofelemer. 2012;. PubMed PMID: 31643647

PubMed Topic Searches

1. PubMed: Croton lechleri (all studies)
2. PubMed: Crofelemer randomised trials
3. PubMed: Taspine
4. PubMed: Sangre de drago / sangre de grado

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Connections

• All Herbs
• Skin, Wound and Topical Herbs — the category this herb belongs to
• Dragon's Blood: Benefits Deep Dive — the evidence ledger and four deep-dive articles
• Crofelemer: From Sap to Licensed Drug — the FDA-approved drug from the latex
• Wound Healing and Insect Bites — the traditional skin uses
• Four Plants, One Name — Croton, Dracaena and the rattan palm
• Taspine, Toxicity and Safety Unknowns — the alkaloid and the mutagenicity findings
• HIV/AIDS — the condition crofelemer was approved for
• Chronic Diarrhea — causes and evaluation
• Irritable Bowel Syndrome — where a crofelemer trial missed its main goal
• Cystic Fibrosis — the CFTR chloride channel crofelemer blocks
• Grape Seed Extract — another proanthocyanidin source
• Cat's Claw — another Amazonian medicinal plant
• Comfrey — a wound herb with an internal toxicity problem
• Self-Heal — another traditional wound herb
• Wound Healing — remedies and evidence for wound care

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