Gotu Kola (Centella asiatica)

What it is

Gotu kola, known in English as Asiatic pennywort, grows as a creeping plant in damp areas of South and Southeast Asia. The stems, leaves and flowers are used, sold as tea, powder or extract in capsules. The plant has a long tradition in Ayurveda and Chinese medicine. Be careful with the name: gotu kola is sometimes also called brahmi, as is the entirely different herb Bacopa monnieri. The European Pharmacopoeia contains its own test for adulteration with bacopa.

The most important constituents are triterpenes: the saponins asiaticoside and madecassoside and their core structures asiatic acid and madecassic acid. The vein studies did not use the herb itself, but a purified triterpene fraction made from it, abbreviated TTFCA. Cosmetics sometimes contain individual saponins such as asiaticoside. Herb, extract and purified fraction are therefore not the same, even if all of them say gotu kola.

How it is supposed to work

In cell and animal experiments, the triterpenes stimulate fibroblasts to produce more collagen I and promote growth factors for new blood vessels. At the same time, they dampen inflammatory messengers such as interleukin-6 and TNF-alpha. This is the source of its reputation as a plant for wounds, scars and skin. For the veins, the effect on the smallest vessels matters most: in studies, the rate at which fluid leaks into the tissue of the ankles decreased, and the oxygen supply to the skin improved.

In humans, at least absorption has been demonstrated. In a small phase 1 study with 4 older people, asiatic acid and madecassic acid appeared in the blood after a water extract, whereas the original saponins did not. In parallel, the activity of NRF2, a switch for the body’s own protective enzymes, changed in blood cells. Whether this has any effect in everyday life is open.

Herb, extract or purified fraction

The studies used very different preparations. In the vein studies it was 30 to 120 mg of TTFCA per single dose, one to three times daily over 4 to 8 weeks. In the 2026 skin study, women took 200 mg of a standardized extract; in a diabetes study, there was 1,200 mg of extract daily; and in a study on anxiety, healthy people swallowed 12 g of powder once. The European assessment gives daily amounts of 40 mg to 12 g for the studies overall.

For you this means: results from a study apply first of all to exactly that preparation. A tea or an untested powder is not automatically comparable with a purified triterpene fraction.

What the studies show

Venous insufficiency, review 2013

The systematic review pooled 8 studies from 1981 to 2001, each with 17 to 99 participants and lasting 4 to 8 weeks, almost all against placebo. Skin blood flow values and ankle swelling improved significantly under the triterpene fraction. The authors urge caution because most studies were poorly reported and their risk of bias remained unclear. Four of the eight studies appeared in 2001 in the same supplement issue of the journal Angiology and come from the same research group.

Wrinkle depth after oral intake, 2026

112 middle-aged Korean women took 200 mg of a standardized extract or placebo daily for 12 weeks, double-blind. Mean wrinkle depth around the eyes decreased by 11.1 percent and the depth of the largest wrinkle by 14.4 percent, both more than under placebo. For maximum wrinkle depth, the difference from placebo was not significant. Moisture and elasticity rose by only 2.7 and 0.7 percent, which the authors themselves describe as modest. The study had no external funding.

Brain and mood, meta-analysis 2017

A meta-analysis evaluated 5 studies with gotu kola alone and 6 with combination products. In no domain of cognitive performance, neither memory nor attention nor processing speed, was there a difference from placebo. Self-rated alertness rose slightly, and anger one hour after intake decreased. The positive individual findings come mainly from one study with 28 older people, divided into four groups.

Blood sugar in type 2 diabetes, 2025

70 people with type 2 diabetes took 1,200 mg of extract or placebo daily for 6 months; the study was preregistered. In the prespecified analysis, long-term blood sugar, fasting blood sugar and LDL cholesterol did not differ between the groups. The product was well tolerated; 5 of 34 participants had mild, transient gastrointestinal complaints.

Startle response, 2000

40 healthy people received 12 g of gotu kola or placebo once. Half an hour and one hour later, the startle reflex to a loud noise was markedly dampened under gotu kola, a possible indication of an anxiety-relieving effect. Mood, pulse and blood pressure did not change. Whether this helps in anxiety disorders was not studied.

Where the data stop

The vein studies mainly measure blood flow values, that is, intermediate values; they are small and date from 1981 to 2001. We did not find any newer independent studies. The European Medicines Agency considers the studies on wounds, skin aging, anxiety and cognitive performance methodologically insufficient to recognize a well-established use.

For the brain, the best available analysis speaks against a measurable effect on memory and concentration. In older people with mild cognitive impairment, gotu kola added to a training program brought no further benefit for cognitive performance. For blood sugar, the longest and best-planned study found no effect. For the skin, there is so far only a single controlled study on oral intake. And because herb, extract and purified fraction are so different, it is hardly possible to say which product has which effect.

Status, approval and legal

According to the EU Novel Food Catalogue, the stems, leaves and flowers of Centella asiatica are considered not novel; member states report their use as an infusion and in dietary supplements. The herb may therefore be marketed as a food in Germany. At the same time, the federal and state substance list (Stoffliste) lists it as a medicinal substance in List B: above a pharmacologically effective amount, a product is considered a medicine. An extract standardized to 40 percent triterpenes, by contrast, is an unauthorized novel food. The 2022 EU monograph recognizes only external use for healing small wounds as a traditional herbal medicine. Health claims on veins, the brain, the heart, digestion and wound healing are on hold at EFSA; advertising with them is not permitted. There is no doping relevance.

Safety

In the studies, gotu kola was mostly well tolerated; the most common complaints were nausea and stomach problems, in one diabetes study in 14.7 percent of participants. Rare liver damage weighs more heavily: a 2005 case series describes 3 women with liver inflammation after 20 to 60 days of use; in one of them, the damage returned after renewed use. In Latin America, gotu kola is among the most frequently named herbal triggers, often in weight-loss products. Because of concerns about the liver and fertility, the European Medicines Agency did not include oral use in its monograph; in rat experiments, high doses damaged the liver and fertility. If you have liver disease, are trying to conceive, are pregnant or breastfeeding, or are allergic to plants of the carrot family, you should avoid gotu kola. Caution is advised with sedative medicines. In case of dark urine, yellowing of the eyes or upper abdominal pain, stop immediately and have it checked by a physician. There are no official maximum amounts.

Sources

• Chong & Aziz, Evid Based Complement Alternat Med 2013
• Puttarak et al., Sci Rep 2017
• Hur et al., Nutrients 2026
• Kongkaew et al., J Cosmet Sci 2020
• Tawanwongsri et al., Front Pharmacol 2025
• Bradwejn et al., J Clin Psychopharmacol 2000
• Jorge & Jorge, Rev Esp Enferm Dig 2005
• EMA, assessment report Centella asiatica herba 2022
• LiverTox, Centella asiatica
• European Commission, Novel Food Catalogue: Centella asiatica