For generations, the vine known across Thailand as โคคลาน or “Koh Khlan” has been a wellspring of traditional healing. Behind this name are other local monikers—มะกายเครือ, มะปอบเครือ, กระเปี้ยะ, โพคาน, แนวน้ำ, เยี่ยวแมว, เยี่ยวแมวเถา—reflecting its widespread recognition in rural and forested communities from the northern hills to the heart of Isan. Scientifically catalogued as Mallotus repandus (Willd.) Müll. Arg., this robust member of the Euphorbiaceae family is best known in Thai traditional medicine for alleviating muscle, bone, and joint pains, often earning its place in time-honoured herbal mixtures for ailments that sap vitality and disrupt daily life.
In an era when modern pharmaceuticals increasingly dominate health conversations, Koh Khlan’s enduring popularity spotlights the powerful role of cultural memory and plant-based wisdom in Thai society. Yet, while elders extol its virtues and traditional doctors rely on its bark, leaves, and woody stems, a new wave of scientific research is illuminating just how much ancient practice and laboratory discovery may converge—and diverge—on the path to better health.
The significance of Koh Khlan in Thai traditional remedies arises from both its complex chemistry and the stories woven into rural life. In villages across Northeast Thailand, local practitioners frequently blend the wood or bark into decoctions intended for those suffering from “kradook jep” (bone pain), chronic stiffness, or muscular injuries from hard labour. Its reputation as a pain reliever is so deep-rooted that it forms the core ingredient in the famed “Ya Pa Som Kho-Khlan,” a pain-relief formula officially listed in the Natural List of Essential Medicines (NLEM) of Thailand (PMID:25629031, pubmed.ncbi.nlm.nih.gov). In some central and northeastern provinces, Koh Khlan is also called upon as an herbal “antibiotic” or for wound healing, a testament to the biodiversity-driven ingenuity built up over centuries (Wikipedia).
Underlying these practices is a philosophy familiar to many Thai readers: balance and harmony, both within the body and between individuals and their environment. The use of Koh Khlan, especially as a component of multi-herb remedies, reflects the longstanding belief that illness is not just a matter of invading pathogens, but a disruption of one’s fundamental equilibrium. For rural healers, the plant’s ability to “cool down” inflammation or relieve chronic soreness resonates with a broader approach that seeks not only to cure, but to restore holistic well-being.
Of course, in the modern context, such beliefs demand careful scrutiny and translation to meet the standards of contemporary science. Over the past decade, researchers have launched a series of laboratory and clinical investigations to better understand what, if anything, validates Koh Khlan’s legendary status.
A landmark 2014 study published in BioMed Research International subjected methanolic extracts of Mallotus repandus leaves to rigorous testing in animal models. The results confirmed that these extracts demonstrated both significant “antinociceptive” (pain-relieving) and anti-inflammatory effects (PMC4297635). Rats and mice treated with the plant extract experienced measurable reductions in induced pain and inflammation, and these effects increased with larger doses. Notably, the extract appeared to work through central and peripheral mechanisms—supporting claims from traditional medical users that Koh Khlan soothes both surface and deep-seated pain.
Phytochemical analysis revealed that Mallotus repandus owes much of its power to a diverse suite of natural compounds, including flavonoids, tannins, and saponins—substances known for their antioxidant and anti-inflammatory potential (PubMed). These compounds, widely studied in modern pharmacology, may help reduce the body’s production of substances (like prostaglandins) that drive pain and swelling. Specifically, laboratory experiments showed that the plant extract suppressed inflammatory cytokines such as TNF-α and IL-1β, while simultaneously boosting anti-inflammatory cytokines (IL-10), hinting at targeted immunomodulating activity (Pharmacy Mahidol).
Further research into the plant’s chemical profile identified the compound bergenin as a major player—one with pronounced anti-inflammatory properties. However, while the whole extract reduced inflammation, researchers found that bergenin alone was less effective, suggesting that the therapeutic power of Koh Khlan depends on the synergistic interplay of its various constituents (Pharmacy Mahidol), a hallmark of traditional multi-herb formulas.
Contemporary investigations have also shed light on Koh Khlan’s antioxidant properties. The ethyl acetate fraction of its stem, in particular, demonstrated notable “superoxide radical” scavenging activity—a key mechanism in lowering oxidative stress and potentially protecting tissues from chronic damage. Such properties not only support traditional claims regarding wound healing and “cooling” actions, but may also position Mallotus repandus as a candidate for further study in combating diseases rooted in inflammation and oxidative imbalance (ScienceDirect).
Across borders, the plant’s reputation extends into folk medicine outside Thailand—in Bangladesh, for example, herbalists use Mallotus repandus to counteract snakebite and soothe itching, while in Taiwan, it features prominently in anti-inflammatory therapies (PMC4297635). Such shared traditions underscore the global resonance of herbal approaches—a point increasingly noted by Thai researchers seeking to integrate indigenous wisdom into evidence-based integrative medicine.
But before anyone rushes to brew Koh Khlan tea or prepare poultices at home, Thai readers should take heed: even natural medicines demand respect, proper knowledge, and caution. Fortunately, safety assessments of the plant have so far been reassuring. Acute and sub-chronic toxicity studies of methanolic extracts showed no signs of kidney, liver, or blood toxicity in animal models—even at very high doses (ResearchGate). Traditional use in multi-herb formulas further mitigates risk, as dosage and preparation are typically governed by practitioners’ experience. Still, long-term safety in humans remains insufficiently documented. Caution is crucial for those with preexisting health conditions, pregnant women, and anyone taking prescription medicines. Potential allergic reactions or interactions, while rare in reported literature, remain possible. Always consult a qualified healthcare provider or licensed Thai traditional medicine practitioner before trying new herbal remedies—especially for chronic or serious illnesses.
The cultural resonance of Koh Khlan is inseparable from its ecological and societal context. In Thailand, herbal medicine is not just about the chemical constituents of plants; it is a living inheritance from past generations and a reflection of local biodiversity stewardship. Community forest networks and local healers often guard this botanical heritage, while academic and governmental initiatives work to formally document, conserve, and standardize traditional knowledge.
Events like seasonal “forest walks” (เดินป่า) in Isan see community elders leading youths to identify and collect healing plants, passing down not just knowledge but ethics—a tradition that embodies the interconnectedness of humans and the natural world. In this tapestry, Koh Khlan is much more than just a medicine; it is a symbol of continuity, adaptability, and hope—a thread woven through both rural memory and progressive health policy.
Looking ahead, the future of Koh Khlan rests in bridging these two worlds. As integrative medicine continues to gain ground in Thailand and globally, Koh Khlan stands as a fascinating exemplar of how plant-based therapies can inform, complement, and challenge biomedical paradigms. Further clinical trials in humans—focusing on efficacy, standardization, and long-term safety—are needed before Mallotus repandus can achieve its full potential as a mainstream intervention for musculoskeletal pain and inflammatory conditions. Meanwhile, conservation of the plant’s natural habitat and sustainable harvesting practices must remain priorities to safeguard both environmental health and continued cultural relevance (Wikipedia).
For health-conscious readers in Thailand, the lessons are clear:
- Recognize the value of time-honoured remedies like Koh Khlan, but pair traditional wisdom with the latest scientific insight.
- Use herbal medicines only under expert supervision, ideally with proper diagnosis and ongoing monitoring by trained professionals.
- Stay informed about the latest findings—whether from Thai universities, international journals, or local practitioners.
- Support efforts to conserve Thailand’s medicinal plant diversity and the cultural knowledge that sustains it.
Ultimately, Koh Khlan’s journey from village forests to scientific journals reflects not just a plant’s healing power, but the broader capacity of Thai society to integrate the best of the old with the hopes of the new.
This article is for educational purposes only. Always seek advice from a qualified healthcare provider before considering any form of herbal or traditional remedy, especially in the presence of pre-existing medical conditions or when taking prescribed medications. The efficacy and safety of herbal medicines can vary based on preparation, dosage, and individual health status.
Sources:
- Analgesic and Anti-Inflammatory Activities of Leaf Extract of Mallotus repandus (Willd.) Muell. Arg.
- Combining DNA and HPTLC profiles to differentiate a pain relief herb, Mallotus repandus, from plants sharing the same common name, "Kho-Khlan".
- Phytochemical screening of Mallotus repandus
- Mallotus repandus - Wikipedia
- Mallotus repandus toxicity studies
- ScienceDirect: Mallotus repandus antioxidant research