For centuries, the humble leaves of khlu, known botanically as Pluchea indica (L.) Less., have quietly woven themselves into the tapestry of Thai traditional medicine. Heralded in folklore from Isan to the Southern provinces, this plant—also called หนาดงั่ว, หนวดงิ้ว, เพี้ยฟาน, ขลู, คลู, and ขี้ป้าน, depending on local dialect—has been held as a village remedy for everything from inflamed joints to kidney health. Today, Pluchea indica stands at a fascinating crossroads, with a growing body of research seeking to validate and explain the benefits extolled by generations of healers. How does ancient wisdom surrounding khlu measure up to the scrutiny of modern science, and what should health-conscious Thais know about harnessing its potential responsibly?
Khlu grows wild across Thailand’s marshes, tidal flats, and roadside ditches. The shrub doesn’t beg for attention—its slightly pungent aroma and simple, oblong leaves often identified as much by sight as by folk memory. In Thai culture, khlu is far more than just a weed. Traditionally, various parts of the plant are put to use: the stem ground for kidney stones, the bark for hemorrhoids, and notably, the leaves—often brewed as a tea to ease inflammations, urinary difficulties, or minor infections, and sometimes folded into local cuisine as a pungent herbal flavoring or dietary component. The persistence of khlu’s use across so many regions of Thailand underscores its place in the country’s mosaic of folk medicine, representing the belief that health is rooted in one’s immediate natural environment (medthai.com).
The plant’s widespread presence and deep roots in Thai life have caught the interest of modern researchers, both for its ethnobotanical importance and its abundance of unique phytochemicals. Modern scientific explorations into Pluchea indica have largely centered on its pharmacological properties, trying to vet age-old beliefs with data, measure active compounds, and test their effects in laboratory and clinical settings. In recent years, scientific journals have published detailed reviews and preclinical studies, positioning khlu as a plant of real medicinal interest (Mahidol University Pharmacy Journal; ScienceDirect).
Traditionally, the most common method of consuming khlu is as a hot water infusion; a handful of fresh or dried leaves steeped and sipped as tea, often without sweeteners, as the slightly bitter flavour is regarded as part of its therapeutic profile. Folk wisdom holds that this preparation helps “cool the body,” reduce inflammation, and gently encourage urination—helpful for those who feel unwell, bloated, or sluggish. In village settings, elders might recommend khlu tea for those suffering from minor fevers, coughs, or “heatiness,” reflecting a holistic approach inspired by the body’s perceived elemental imbalances.
Modern science reveals that many of these traditional uses are not unfounded. Key phytochemical investigations have identified chlorogenic acid, caffeic acid, quercetin, carotenoids, and flavonoids in the leaves—compounds documented for their antioxidant, anti-inflammatory, and even antimicrobial activity (Mahidol Pharmacy Journal PDF). Such antioxidants are important in neutralizing free radicals, substances known to damage cells and potentially contribute to chronic diseases.
Preclinical studies have confirmed that ethanolic extracts of Pluchea indica leaves possess significant antioxidant capacity, which helps explain some of the plant’s purported benefits in supporting cardiovascular health and reducing chronic inflammation (NCBI). Laboratory research also suggests that extracts may help inhibit certain bacteria, fungi, and parasites, potentially providing scientific support for the plant’s traditional role in combatting gastrointestinal tract infections such as dysentery and leucorrhoea (ScienceDirect review; PubMed).
The anti-inflammatory activity of Pluchea indica is particularly intriguing to scientists. Studies isolated multiple active compounds that can inhibit nitric oxide production and reduce the activity of pro-inflammatory enzymes—key mechanisms involved in swelling, pain, and the body’s response to infection or injury (MDPI review). The roots and bark, too, have been found to contain similar anti-inflammatory agents, lending credence to the plant’s broad range of applications in folk medicine.
These laboratory results, while promising, mostly come from in vitro (cell-based) or animal experiments. Human clinical research is still in early stages. One Thai study published in a urology journal found that consuming Pluchea indica infusions could have a mild diuretic effect in healthy volunteers—a result that mirrors its historical use as a natural remedy for water retention and certain urinary tract complaints (medplant.mahidol.ac.th). However, neither this nor other modest studies yet provide sufficient evidence to definitively recommend the plant for preventing or treating diseases like kidney stones, despite centuries of use.
Culturally, khlu’s popularity reflects not just therapeutic hopes but Thai attitudes toward balance, self-care, and respect for local ecology. In many rural and peri-urban Thai communities, khlu remains a common home garden plant. Elders will tell stories of using its fresh leaves to soothe rashes, wrap herbal compresses, or even as a dietary ingredient in som tam or yum salads, believing that its strong aroma helps “clear bad humors.” Some Buddhist merit-making ceremonies in the South also use bundles of khlu as symbolic offerings of purity and healing—a reminder of the plant’s sacred association with health and renewal (Thai Traditional Food).
With interest in local superfoods and natural therapies on the rise—fueled in part by movements for sustainable living and “food as medicine”—khlu is enjoying renewed attention among young Thais, chefs, and wellness practitioners. Some see it as a green local alternative to imported herbal teas, and many home cooks embrace it for its distinct flavor and perceived wellness benefits.
Yet, the surge of enthusiasm requires a careful and educated approach. Although preclinical studies have seldom flagged Pluchea indica as highly toxic, the concentration and frequency of consumption matter. The plant’s diuretic effects, for example, could pose risks for those with certain kidney conditions or those already taking medication affecting fluid balance (Mahidol Pharmacy Journal PDF). As with any herbal medicine, adverse reactions, allergic sensitivities, and interactions with pharmaceutical drugs are possible, and the lack of large-scale clinical data means that standardized dosing and comprehensive safety profiles are still evolving topics. Thailand’s Food and Drug Administration (อย.) classifies Pluchea indica primarily as a traditional herbal product, not as a licensed pharmaceutical; consumers should be aware that quality and potency can vary between preparations and brands.
Many local health educators stress that no plant, no matter how promising, should substitute for medical treatment, especially in cases of serious or chronic illness. For everyday wellness, khlu tea may be enjoyed as part of a balanced diet, with awareness of one’s health conditions and in consultation with healthcare professionals. It exemplifies an approach to wellness grounded in tradition, but the gold standard of modern medicine—which demands rigorous, large-scale, placebo-controlled clinical trials—has not yet been fully achieved for this plant.
Looking forward, the future of khlu as an herbal medicine in Thailand may depend on bridging the confidence of heritage healers with the caution of scientific validation. Researchers continue to investigate its unique chemistry, its applications for infectious and inflammatory diseases, and its underlying mechanisms. There is potential, too, for economic benefit: expanded cultivation and quality-controlled production could enable exports to global markets, especially as consumers worldwide become more curious about Thailand’s treasure trove of native medicinal plants.
For practical, health-conscious readers, the best path to enjoying khlu’s potential benefits is through moderation, curiosity, and diligence. Try khlu tea fresh from your local market—after confirming identification and ensuring ethical sourcing. Use it as a complement to a healthy lifestyle, not as a cure-all. Stay informed by following respected Thai and international health news and by consulting reliable online resources such as Mahidol University’s herbal information portal and Medthai, as well as your healthcare provider, before embarking on any new regimen involving herbal medicines.
In embracing khlu—like so many of Thailand’s herbal wonders—one honors not only a remarkable plant, but the wisdom of Thai ancestors and the ongoing journey of scientific discovery. As global and local interest in plant medicine continues to grow, khlu’s story is still being written—grounded in the past, blooming into the future.
This article is for educational purposes, intended to share information about traditional herbal medicines. It is not a substitute for medical advice. Readers are urged to consult a qualified Thai healthcare provider before using khlu or any other herbal remedy, especially if they have underlying medical conditions or are taking prescription medications.
References:
- Mahidol University Pharmacy Journal: Abstract in English
- Mahidol University Pharmacy Journal: PDF in Thai
- Medthai: ขลู่
- NCBI Article: Ethanolic extracts and antioxidant capabilities
- ScienceDirect: Antimicrobial and traditional uses
- MDPI: Pharmacological activities
- Mahidol: Human diuretic study
- Thai Traditional Food on Pluchea indica