Euphorbia resinifera
Plant Family
Euphorbiaceae.
Binomial Name, Author
Euphorbia resinifera O.Berg in O.Berg & C.F.Schmidt
Synonymous Binomial Names
Euphorbia resinifera var. chlorosoma Croizat
Euphorbia resinifera f. compacta hort.
Euphorbia resinifera var. typica Croizat
Euphorbia sansalvador hort. ex H.Jacobsen
Tithymalus resiniferus (O.Berg) H.Karst.
Tithymalus resiniferus (O.Berg) H.Karst.
Common (Vernacular) Names
African spurge, Euforbium, Euphorbe, Euphorbium, Euphorbium Resinifera, Farbiyun, Gum euphorbia, Moroccan ground spurge, Moroccan mound, Moroccan mound spurge, officinal spurge, Poisonous gum-thistle, Resin spurge, Spurge, Wolf’s milk.
Plant Characteristics
Endemicity. It is native to central Morocco, in the Azilal and Beni Mellal regions (Middle Atlas), with some scattered populations in the High Atlas and Anti-Atlas Mountains (Moujanni et al. 2017).
Growth Habit. A succulent, low growing, usually leafless, evergreen, succulent spiny shrub. Shoots from the base of the plant are ascendant, four sided with ridges between the sides. The ridges have pairs of short (6mm), sharp spines, about one centimeter apart. Branches form off the main shoots. It grows slowly forming dense cushioned-shaped mounds of a maximum height of about 60 cm (2 feet) and 2m (6 feet) wide. The leaves, if present are inconspicuous.
 Euphorbia resinfera |
Flowers, Fruits and Seeds. The flowers are small, simple, and bright yellow, and the fruit a small capsule with one seed in each cell. Flowering is rare out of its native range (Martin 2018) and our plants have not bloomed in Hawai‘i.
 Euphorbia resinifera, Flowers |
Conservation Status
This species is abundant in its range and not regarded as threatened or endangered.
CITES Listing: All of the succulent Euphorbia species including Euphorbia resinifera are listed on CITES Appendix II (CITES 2018).
IUCN Listing: No assessment of this species was found on the IUCN Red List of Threatened Species™ [IUCN 2018].
U.S. Endangered Species Act Listing Status: Not listed (FWS 2018).
Sustainable Harvesting and Sourcing. About 40 liters of resin from Euphorbia resinifera were imported into the United States for the initial research at the National Institutes of Health (NIH). The NIH team worked with Ahmed Benharref, of the Laboratory of Natural Chemical Products at the Université Cadi Ayyad in Marrakech, and Charles Dahan, of the United States and Morocco, who handled international coordination and export licensing. The sap is collected from the plant by scoring the surface of the shoots and branches. This does not damage the plant (Ross 2006).
Uses
Ancient Medicinal Uses
The following information was compiled from translations of Pliny the Elder’s Naturalis Historia , Dioscoride’s De Material Medica (Osbaldeston and Wood 2000) and references by Dale (1985), Appendino and Szallasi (1997), LLifle (2018) and others.
Euphorbia resinifera, known as Officinal Spurge, Resin Spurge and by other names, is one of the oldest documented medicinal plants. The extracted, sun dried, latex-like sap called Euphorbium, probably came from this plant and was used as a purgative, emetic, treatment for snakebite and other medicinal purposes for at least 2,000 years.
(The common name “spurge” derives from the Middle English/Old French espurge (“to purge”), due to the use of the sap from plants in this group as a purgative).
Euphorbus was the Greek physician of Juba II of Numibia (52-50 BC – 23AD) who married Cleopatra Selene II, the daughter of Antony and Cleopatra. In 40 BC Euphorbus wrote that a plant discovered in the Atlas mountains, (probably Euphorbia resinifera) was a powerful laxative. In 12 BC, Juba named this plant Euphorbia, after his physician Euphorbus. In response, Emperor Augustus dedicated a statue to Antonius Musas, Augustus’s own personal physician and Euphorbus’ brother (Dale 1985).
Pliny the Elder. In the encyclopedic works of Naturalis Historia (published 77-79 AD), Pliny refers to this plant by various similar names: euphorbia, Euphorbeum and euphorbium. References to medicinal uses of the plant appear in multiple books of Naturalis Historia:
A) In Book V, I: treatment for snakebite and an antidote for poisons-
“…It is well ascertained that the next people are the Aethiopian tribe called the Perorsi. Juba, the father of Ptolemy, who was the first ruler to hold sway over both the Mauretanias, and who is even more distinguished for his renown as a student than for his royal sovereignty, has published similar facts about Mount Atlas, and has stated in addition that a plant grows there called the euphorbia, named after his doctor who discovered it; in a volume devoted solely to the subject of this plant he sings the praises of its milky juice in very remarkable terms, stating it to be an aid to clear sight and an antidote against snakebite and poisons of all kinds.—This is enough, or more than enough, about Mount Atlas.”
B) In Book XXV, XXXVIII, “the natures of self-grown plants; value of plants” –treatment of snakebite:
“It is employed as treatment for snakebite. In whatever part of the body the bite may be, an incision is made in the top of the skull and the medicament inserted there. The Gaetulians who gather the juice adulterate it out of weary disgust by adding milk, but fire is a test of genuineness, for that which is adulterated emits a nauseating smell.”
Here, the method of collecting the sap and preparation of Euphorbium is also described:
“In the age too of our fathers King Juba discovered a plant to which he gave the name euphorbea, calling it after his own physician Euphorbus. …But the treatise also of Juba on this plant is still extant, and it makes a splendid testimonial. He discovered it on Mount Atlas; it has the appearance of a thyrsus and the leaves of the acanthus. Its potency is so great that the juice, obtained by incision with a pole, is gathered from a distance; it is caught in receivers made of kids’ stomachs placed underneath. Fluid and like milk as it drops down, when it has dried and congealed it has all the features of frankincense. The collectors find their vision improved.
C) In Book XXV, XCI: …. Euphorbeum too improves the vision of those whose eyes are anointed with it…
D) In Book XXVI, XXXIV: Use as an aperient (purgative) –“…euphorbeum or agaric, in doses of two drachmae with a little salt, taken in water or in three oboli of honey wine”.
E) In Book XXVI, LXXII: Use to waken sufferers from lethargus – “…this is done by touching the nostrils with euphorbeum in vinegar, or with the juice of peucedanum.”
F) In Book XXVII, I: …To think that the Scythian plant, for example, is brought from the marshes of Maeotis, euphorbea from Mount Atlas and from beyond the pillars of Hercules, where the works of Nature actually begin to fail;…
Dioscorides. Dioscoride’s De Materia Medica (Osbaldeston and Wood 2000) written in 50-70 AD, was one of the most influential herbal books in history and a precursor to all modern pharmacopeias. Use of Euphorbium was included Materia Medica. In the English translation, the reference in section 3-96 EUPHORBION, is stated to be to two species: Euphorbia amygdaloides – (Wood Spurge) and Euphorbia officinarum “Poisonous Gum Thistle”, (which was probably Euphorbia resinifera). Euphorbia amygdaloides is a bushy herbaceous plant native to Europe, Turkey and the Caucasus The translated text in De Meteria Medica describes Euphorbium as a tree-like ferule in Libya. That does not appear to be a correct description of either of these species, which are not tree-like, nor their endemicity. Pliny referred to euphorbea as from Mount Atlas. Perhaps this confusion may be explained by errors in translation, geographic names or plant nomenclature. Dioscoride’s description of the method for collecting the sap and some of its uses is similar to that of Piney. He also describes additional uses of it in mixtures of other ingredients, including a treatment for sore hips, for removal of “scales from bones” and as an eye salve and suppository.
Naming of the Genus. In 1753, Carolus Linnaeus, the great taxonomist, assigned the name Euphorbia, to the entire genus of plants in honor of King Juba’s physician Euphorbus.
Declining Use. Dioscoride’s De Materia Medica remained in use until about 1600 AD (Parker 1915). As use of Materia Medica lessened, newer medical texts continued to refer to Euphorbium but descriptions of its indications and use appeared to evolve and became confused. Concerns about its severe toxic effects also grew. By the late 1800s the use of Euphorbium in Western medicine had declined and it was nearly obsolete (Hempel 1880, Brently 1887 and Cowperthwaite 1892). An example of its declining use in Britain:
“Medicinal Properties.—Drastic purgative and emetic when administered internally, but its action is so violent that it is now never employed. At present it is only used externally as a rubefacient and vesicant; and even in these respects, in Britain, its use is almost or quite obsolete, except in veterinary practice.” (Bentley 1887).
Modern Medicinal Uses
The summary information in the following sections relating to medical research was compiled from numerous references. Many of these are cited in the text and additional key publications are included in the reference section.
Discovery of Resiniferatoxin (RTX). Resiniferatoxin, the active principle in Euphorbia resinifera was first identified in 1975 (Hergenhahn, Adolf and Hecker 1975). It is also found in several other species in the genus Euphorbia (Szallasi and Blumberg (1989).
Chemistry. Resiniferatoxin (CAS Registry Number 57444-62-9), is a naturally occurring diterpene found in Euphorbia resinifera and several other species of Euphorbia. It is an ultrapotent analog to capsaicin (the active chemical in chili peppers).
Current Medical Research. Szalliasi and Blumberg (1989) first reported the high potency of RTX and its pain desensitization effects from studies on rats. Some of the early research by Peter Blumberg at the National Cancer Institute leading to new applications of capsaicin and resiniferatoxin is described in the reference by Pollner (1997). RTX is currently the subject of intense medical research interest. A search conducted on PubMed in October 2018 using the search term ‘resiniferatoxin” yielded 907 references. Most of this research is on use of RTX for control of pain.
Mechanism of Action. Resiniferatoxin activates the TrpV1 receptor (transient receptor potential cation channel subfamily V member 1), previously referred to as the vanilloid receptor, in a subpopulation of primary afferent sensory neurons (C-fibers and some A delta nerve fibers) involved in nociception (the transmission of physiological pain). RTX is naturally selective for these nerves, in fact it is so selective it is referred to as a “molecular scalpel” for chronic pain relief (Brown 2016).
As capsaicin binds to TRPV1 receptor it allows the channel gates to open briefly, allowing a limited amount of calcium and sodium ions to enter the cell and generate the burning sensation associated with eating hot chili peppers. RTX, an analog of capsaicin, binds to the receptor from 500-1,000 times stronger than capsaicin, blocking the gates open for a prolonged period. The inflow of these ions through the open gates into the fibers or nerve cell bodies triggers apoptosis (cellular programmed death) within an hour of exposure to RTX. With the death of these cells, pain can no longer be transmitted. Sensations of touch, proprioception, and high-threshold mechanosensitive nociception, as well as locomotor function, remain intact (Karai et al. 2004a,b).
Refer to the excellent reference and video by Ark Animal Health (AAH 2018) for a more detailed and pictorial explanation of the mechanism of action, which was only summarized here.
Method of Application. Some of the earliest clinical trials were conducted to evaluate the potential of resiniferatoxin treatment to relieve pain associated with diabetic polyneuropathy and postherpetic neuralgia. These were performed with topical applications (Appendino and Szallasi (1997). Cystitis other urinary conditions have been investigated and treated by intravesical (in bladder) applications (Guo et al 2013). More recent treatment methods being evaluated for other conditions such as cancer pain involve injections of RTX by a central route into subarachnoid space around the lumbosacral spinal cord, or peripherally. The central route is being evaluated as treatment or intractable pain in patients with advanced cancer. Peripheral administration offers the possibility to treat a wide variety of pain problems at the site of the pain (Iadarola and Gonnella 2013).
Benefits. In 2006 it was estimated that there were 50,000—100,000 cancer patients who either could not control their pain or had a dismal quality of life because of the side effects of their pain medication (Ross 2006).
Resiniferatoxin may offer a safe and effective, non-opioid, long-lasting or single dose treatment for many of the most excruciating and intractable forms of pain for which currently available analgesics may be not be available, are of limited or short term effectiveness or have undesirable side effects and potential for addiction.
RTX can potentially help patients with terminal cancer pain, after a single epidural injection, by permanently blocking the pain signal transmission from the tumor tissue to the dorsal root ganglion (DRG) in the spinal cord, without the undesirable side effects associated with high and repeated doses of opioids. If opioids remain part of the therapeutic arsenal for these patients, RTX has the potential to significantly reduce the amount and frequency of opioids use (STI 2018a).
RTX is unlike anything currently available to manage hard-to-control chronic inflammatory pain (AAH 2018). Most of the currently available data is from preliminary research in animals and these studies have shown that has shown that RTX can reduce pain and appears to be safe (NLM 2018). Data from NIH investigators highlighting results from the first two dosing cohorts of the Phase I/II trial of resiniferatoxin (RTX) for the treatment of intractable cancer pain in human patients were promising (STI 2014):
- Clinically meaningful improvement in quality of life with single injection of resiniferatoxin
- Improvement in pain intensity by 20%, as measured by numerical rating scale, with most patients experiencing increased activity levels
- Resiniferatoxin appears well-tolerated with no opioid-like toxicities.
Other Applications for Pain Control. While the most active area of clinical research is for its potential use in treating the intractable pain of advanced cancer, applications for control of other sources of pain are being studied and the results from preliminary research are hopeful:
- Ophthalmic Pain. Analgesics available for treatment of pain from following ophthalmic surgery or injury are limited by transient effectiveness and undesirable or adverse side effects. Data from one study suggests that RTX may be a safe and effective treatment for this pain (Bates et al. 2010).
- Burns. RTX may provide valuable long-term, non-opioid analgesia for burn patients (Salas et al. 2017).
- Osteoarthritis Pain. Data from one study suggests that a single dose of intra-articular RTX may be an effective intervention for osteoarthritis pain with few or no side effects and lead to an improved quality of life (Iadarola et al. 2018). In August 2018, Sorrento Therapeutics, Inc. announced the results from a clinical trial in which the first patient treated for osteoarthritis knee pain with their resiniferatoxin in a Phase 1B clinical trial. Safety and efficacy expectations were met (STI 2018).
- Incisional Pain. Data from an animal study on rats suggests that RTX may be used to treat pain from surgical incisions. Opioids, such as morphine or fentanyl, are often used for moderate to severe post-operative pain relief, but these often come with side effects that can interfere with recovery, including respiratory depression, inhibition of gut motility and constipation, nausea and vomiting. Prolonged use of opioids can produce tolerance and introduces the risk of misuse. RTX is not an opioid and does not act in the brain but rather on the nerve endings in the skin.
Data from the study indicates RTX can be used to block pain from a surgical incision selectively for approximately 10 days. In the study, researchers pre-treated the skin incision site with RTX to render the nerve endings in the skin and subcutaneous tissue along the incision path selectively insensitive to pain. Unlike local anesthetics, which block all nerve activity including motor axons, RTX allows many sensations, like touch and vibration, as well as muscle function, to be preserved. Long after the surgery, and towards the end of healing of an incision wound, the nerve endings eventually grow back. Thus, pain from the skin incision is reduced during the recovery period but the ability to sense pain may be restored. This new potential use of RTX may help limit patient use of opioid medications while in the hospital and during home recovery. The above information was copied or excerpted from these references: (NIH 2017, Raithel et al. 2018).
Clinical Trials. Data on the safety and effectiveness of RTX in humans will be generated from clinical trials. By late 2018 multiple clinical trials for testing the use of resiniferatoxin to control severe and intractable pain of bone and other cancers, and knee pain in moderate to severe osteoarthritis were being planned and recruiting patients, or in progress (NLM 2018a,b,c,d,e).
A clinical trial to attempt control pain following third molar extraction with capsaicin, another naturally occurring vanilloid compound from plants and analog of resiniferatoxin was also recently concluded (NLM 2018f).
Refer to the ClinicalTrails.gov website for the most current, official information on these clinical trials.
Patents. In 2012 a method patent for the use of RTX was issued to the U.S. Department of Health and Human Services (Iadarola, Olah and Karai 2012) and is administered by the National Institutes of Health (NIH). NIH licensed it to Sherrington Pharmaceuticals, Inc. for collaboration and assistance in moving the drug through clinical development. In 2013 Sherrington was acquired by Sorrento Therapeutics Inc. Five patents relating to resiniferatoxin have been submitted and three have been granted (NCBI 2018d).
Orphan Drug Status. Resiniferatoxin has status as a designated orphan drug for treatment of intractable pain at end-stage disease (FDA 2003). Sorrento is taking the necessary steps to rapidly advance this orphan drug product to registration (STI 2014).
Homeopathic Drug. Euphorbia resinifera resin is available under the proprietary name of Euphorbium Officinarum, generic name of euphorbia resinifera resin, NDC 71919-281, as an over the counter homeopathic drug for use in relieving the symptoms of burning pains. It is in the Marketing Category of an “Unapproved Homeopathic” (NDC 2018). The National Center for Homeopathy lists numerous other clinical applications for Euphorbium (NCH 2018).
Veterinary Use. Dogs and other animals are used in studies to validate the safety and effectiveness of RTX for human use. The data from these studies are now being applied to provide access to new therapeutics for pets that would otherwise never be available.
Arc Animal Health (Ark), a wholly owned subsidiary of Sorrento Therapeutics, applies human therapeutics to treat naturally occurring diseases in companion animals. The first example of this will be for the treatment of pain associated with osteosarcoma in pets. In studies of dogs with advanced cases of this cancer, treatment with RTX led to sustained reduction in levels of pain throughout a 14-week observation period and pain control remained evident throughout the dogs’ remaining life. Ark has submitted sections of a New Animal Drug Application (NADA) for the control of this pain and been granted a Minor Use. They are also planning additional development programs for potential applications in the treatment of osteoarthritis in dogs, idiopathic cystitis in cats, as well as ocular pain and caudal heel pain in horses (AAH 2018).
Non-Medicinal Uses
Xeriscaping. Euphorbia resinifera is excellent for use as a specimen plant in containers and as a sub-shrub or low ground cover succulent in xeriscaping in desert areas. It is highly tolerant of drought, wind, extreme heat, frost and alkaline or saline soils and is a tidy, low maintenance plant with no pests. In Hawai‘i the plant grows well in containers and can be grown in the ground in areas with moderate to low rainfall and well-drained soil. It may benefit from some additions of limestone or coral rock to decrease acidity of volcanic soils. Avoid planting in areas where it may be hazardous to people and pets. (See Toxicity and Precautions section below).
 Euphorbia resinifera, Potted Plant |
 Euphorbia resinifera in Hawaii |
Honey. The monofloral honey produced from Euphorbia resinifera is considered to be one of the most distinguishable, highest quality and valuable honeys produced in Morocco. Moujanni et al. (2017) recently published a detailed physicochemical characterization of the honey.
Educational Displays. We have repeatedly used this plant and Pachypodium ambongense as display specimens in educational programs intended to improve awareness of the importance of plants as sources of important new drug discoveries – such as resiniferatoxin. See the article on Pachypodium ambongense for more information about these displays.
At the 2007 Earth Day and Bring Your Child to Work Day event at the National Institutes of Health in Bethesda, Maryland the Division of Environmental Protection included a specimen of Euphorbia resinifera in a display, and a poster titled “From Nature to Bedside”, was presented highlighting the story of efforts to develop extracts from the plant into a new treatment for cancer pain. The poster title was derived from the NIH Bench-to-Bedside (BtB) Program, which funds research teams seeking to translate basic scientific findings into therapeutic interventions for patients and to increase understanding of important disease processes (NIH 2018). Funding from the BtB program was used for some of the initial animal research work on resiniferatoxin, the purchase of the initial Euphorbia resinifera latex from Morocco, and the costs of drug purification to meet FDA regulatory guidelines (Waring 2007).
The 2007 event also included a large specimen of Euphorbia ingens, a related African Euphorbia species known as the candelabra tree or naboom, for a “hands-on” demonstration showing children how sap can be collected for research from these types of plants without harming them. The photo below is of Dr. Mike Iadarola, one of the most prominent researchers on resiniferatoxin, helping a younger researcher collect the sap.
 Dr. Michael Iadarola and Young Researcher |
Cultivation
The plant has been in wide cultivation in California and Arizona as a landscaping plant for many years and used as a houseplant or for interiorscaping. We could find no records of this plant in Hawai‘i before we introduced it here in March 2013. Some plants of this species have been sold and are presumably now in cultivation in the K’au District of the Big Island. It is also available from mail order nurseries located on the mainland.
Propagation
Seeds. The plants can be propagated by seed sown indoors in early spring.
Cuttings: The plant is usually propagated from stem segments (propagules). Rinse off the sap from the cuttings and allow them to dry for about a week before planting to reduce the potential for rot. Most of the cuttings will root but this may take several months.
Improved Cultivars
Three subspecies, varieties, forms or cultivars of Euphorbia resinifera are listed in the Encyclopedia of Succulents (LLIFLE 2018):
Euphorbia resinifera f. compacta hort. A shorter, compact form.
Euphorbia resinifera f. monstruosa hort.: A form that produces many small, compact branches along the stem.
Euphorbia resinifera O.Berg in O.Berg & C.F.Schmidt: A small, rapidly suckering plant that will form dense multi-stemmed cushion-shaped clumps up to 2 m wide.
Pests and Diseases
Plants kept in wet, poorly drained soil may develop rot. No other pests or diseases of this plant have been reported. Deer and wild pigs do not consume it.
Invasiveness Potential
Hawai‘i-Pacific Weed Risk Assessment (HPWRA) Program. We requested the program to assess the invasiveness potential of Euphorbia resinifera since there were no records of prior introductions in Hawai‘i. HPWRA accessed it in 2015 and assigned it a risk assessment score of 2, indicating low risk.
Global Invasive Species Database Listing. This species was not found on the database (GISD 2018).
Toxicity and Precautions
Avoid all skin and eye contact with the latex-like sap that is exuded from the plant wounds. When handling the plant wear gloves, goggles and other Personal Protective Equipment (PPE) as appropriate for protection against the plant’s sap and thorns. Sap, particularly when dried on the skin or other surfaces may be difficult to remove and may persist for extended periods of time. Use of disposable PPE that does not require decontamination may be preferable.
It may not be advisable to plant this near walkways or in areas accessible to pets or children. We do not advocate use of this plant for landscaping purposes in Hawai‘i.
 Euphorbia resinifera, Sap Flow |
Plant Toxicity. All parts of the plant are toxic. However, the severity of symptoms from ingestion and skin contact may be lower than some other Euphorbia species. A reference by the North Carolina State University Extension indicates that ingestion causes nausea, vomiting and diarrhea; contact with the skin results in blisters after some delay. The severity of symptoms is characterized as: “Causes only low toxicity if eaten. Skin irritation minor or lasting only for a few minutes” (NCSUE 2018).
In our experience in handling the plant and cuttings, skin exposure to the sap has resulted in only minor skin irritation, and no blistering. Skin exposures to the sap of Euphorbia platyclada and E. tirucalli are more irritating and may cause blistering. Exposure of the eyes to even trace amounts of the sap of these species and E. resinifera can cause severe burning, redness and temporary blindness. Routine hand washing after handling these euphorbias may not be effective, leaving sufficient sap contamination on the fingers to cause severe reactions after touching eyes or other sensitive tissues.
Resiniferatoxin (RTX). Purified resiniferatoxin is acutely toxic and one of the most irritating chemicals known. The primary action of resiniferatoxin is to activate sensory neurons responsible for the perception of pain. Exposures to minuscule amounts can severe burns and eye damage. Oral ingestion of sub-microgram amounts result in severe burning pain. Refer to suppliers’ Material Safety Sheets and the PubChem reference for GHS (Globally Harmonized System) Hazard Statements and Precautionary Statement Codes (NCBI 2018).
Plants and Seeds for Sale
Seeds. Not available.
Plants. We have rewumed limited sales of this plant. Cuttings from our Hawaii grown plants may be made available to bona fide institutions for research and educational purposes. Sales to others may be restricted. Please contact us for further information.
Improved Cultivars. No improved cultivars of this species have been developed.
Shipping Information
Domestic shipments: We cannot ship non-certified plants and cuttings to the states of Arizona, California, Louisiana or Texas. Certified plants can be shipped to all states. Exceptions may apply to shipments of plants for research or other non-propagative purposes.
International shipment: Because this plant is CITES regulated (listed on Appendix II) we are not currently permitted to ship it to destinations outside the U.S.
References
AAH (Ark Animal Health) 2018. Resiniferatoxin (RTX) a novel non-opioid solution aimed at intractable pain. http://www.arkanimalhealth.com/resiniferatoxin [accessed 28 October 2018].
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Bates BD, Mitchell K, Keller JM, Chan CC, Swaim WD, Yaskovich R, Mannes AJ, Iadarola MJ. 2010. Prolonged analgesic response of cornea to topical resiniferatoxin, a potent TRPV1 agonist. Pain 149(3):522-8. Epub 2010 Apr 18. PMID: 20403666 PMCID: PMC2913152 DOI: 10.1016/j.pain.2010.03.024.
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Disclaimers:
On this page we have attempted to summarize information about Euphorbia resinifera, including its toxicity and research on potential medical applications of resiniferatoxin, a compound derived from it. We have obtained this information from sources that we believe to be trustworthy. However, the data presented here should be considered provisional, incomplete and may not definitive. Refer to peer-reviewed published scientific references and official agencies for definitive information, and to health care medical professionals for medical advice.
No statements on this website and none of our products are intended for use in diagnosing, treating, curing or preventing any diseases of humans, animals or plants. None of these statements or products have been evaluated by the U.S. Food and Drug Administration (FDA).
Page Last updated 26 February 2022.