Centella asiatica, also called Cica or Gotu kola, is a plant-derived botanical ingredient whose most studied components are triterpenes, especially asiaticoside, madecassoside, asiatic acid, and madecassic acid, and human research has examined it in topical skin formulas, oral microcirculation studies, cognitive studies, anxiety physiology, diabetic skin or microvascular contexts, and oral pharmacokinetic studies (Review).
Centella asiatica is studied in two main ways: topical application for skin outcomes and oral ingestion for systemic outcomes such as microcirculation, cognition, and pharmacokinetics (Review). The strongest human evidence is formulation-specific topical skin research and oral venous or microcirculation research, while evidence for cognition, anxiety physiology, and pain is more limited or mixed (Review). For skincare readers, the key point is that topical percentages such as 0.05% w/w ECa 233 gel, 2.5–5% Centella extract formulations, or 7% Centella extract cream describe the studied product formula, not the exact amount of purified active triterpene delivered into skin (Research) (Review).
Ingredient Identity
- Official name(s): Centella asiatica (L.) Urb.
- Common names: Cica, Gotu kola, Indian pennywort, tiger grass.
- Classification: Botanical ingredient; source of pentacyclic triterpenes and triterpene glycosides (Review).
- Key studied components: Asiaticoside, madecassoside, asiatic acid, and madecassic acid are the main Centella triterpenes most often discussed in skin, pharmacokinetic, and mechanistic research (Review).
- Other studied components: Some oral pharmacokinetic research also measures caffeoylquinic acids, a group of plant polyphenols abbreviated as CQAs in pharmacology studies (Research).
- Endogenous vs exogenous: Centella asiatica is exogenous, meaning it is a plant-derived ingredient and not a compound normally produced by the human body (EMA).
- Common research formats: Topical creams, topical gels, scar formulas, oral triterpene fractions, standardized extracts, crude herb preparations, and oral pharmacokinetic extract studies (Review).
Ingredient Snapshot
- Classification: Centella asiatica is a triterpene-rich botanical ingredient studied in both dermatology and oral herbal-extract research (Review).
- Endogenous vs exogenous status: It is an exogenous plant ingredient rather than an endogenous human metabolite (EMA).
- Primary human research domains: Human studies most often examine Beauty and Skin Health, Cardiovascular Health, Diabetes and Glycemic Control, Cognitive Health, Mental Health, and exploratory Pain and Acute Inflammation contexts (Review).
- Common study formats: Skin studies use creams, gels, or combination scar formulas, while oral studies use standardized extracts, crude herb, or triterpene fractions such as TTFCA, meaning total triterpenic fraction of Centella asiatica (Research) (Research).
- Pharmacokinetic characterization status: Human pharmacokinetic research has measured Centella triterpenes in blood and urine after single oral 2 g and 4 g doses of a standardized Centella asiatica water extract product, abbreviated CAP in that study (Research) (Research).
- Regulatory context, U.S.: In the United States, dietary supplements are regulated under a framework separate from drugs, and FDA generally does not approve dietary supplements before marketing (FDA).
- Regulatory context, EU: The European Medicines Agency has reviewed Centella asiatica herb in an herbal-medicine assessment context, including oral use, topical use, human studies, and safety considerations (EMA).
- Evidence maturity: The evidence is moderate but formulation-specific for skin and microcirculation research, and more limited or mixed for cognition, anxiety physiology, and pain (Review).
Introduction
Centella asiatica, also called Cica or Gotu kola, is a creeping plant whose best-studied components are asiaticoside and madecassoside, which are triterpene glycosides, and asiatic acid and madecassic acid, which are triterpene aglycones, or non-sugar forms of those related compounds (Review). In simple terms, these triterpenes are the main Centella constituents researchers track when studying skin repair, scar appearance, oral absorption, and microcirculation outcomes (Research).
Centella is widely looked up because it appears in both “cica” skincare and Gotu kola supplement contexts, but the evidence should be read by route and formulation rather than by ingredient name alone (Review). Topical human studies have examined Centella-containing creams and gels for post-laser redness, scar appearance, hydration, wrinkles, and stretch-mark prevention, while oral studies have examined venous microcirculation, diabetic microangiopathy, cognitive outcomes, anxiety physiology, pain, and pharmacokinetic markers (Research) (Research).
This article is informational only, describes Centella asiatica as a botanical substance studied in human research, and does not provide medical or dosing advice.
Quick Summary
- Centella asiatica is a plant-derived ingredient studied both topically and orally, and the route of use changes what the evidence means (Review).
- The main studied components in Gotu kola are asiaticoside, madecassoside, asiatic acid, and madecassic acid, which are triterpene compounds linked to much of the ingredient’s skin and pharmacokinetic research (Review).
- Topical Centella research supports cautious, formulation-specific claims for post-laser recovery, scar appearance, hydration, wrinkles, and stretch-mark prevention, but it does not establish one ideal cica percentage for all skincare products (Research) (Review).
- Some topical concentration data exist, including 0.05% w/w ECa 233 gel, 2.5–5% Centella extract cosmetic formulations, and 7% Centella extract cream, but those percentages describe product concentration rather than pure active-triterpene delivery (Research) (Review).
- Oral vascular studies often used TTFCA, meaning total triterpenic fraction of Centella asiatica, so 90–180 mg/day in those studies refers to a triterpene fraction and not to ordinary Gotu kola leaf powder (Research).
- Human cognitive and anxiety evidence exists, but systematic review findings do not show strong, consistent cognitive effects across studies (Review).
- Human pharmacokinetic studies found measurable asiatic acid and madecassic acid in plasma after oral standardized Centella water extract, while parent glycosides were not detected in plasma in the healthy older-adult study (Research).
Human Research Findings by Condition
Beauty and Skin Health
Human skin research on Centella asiatica includes randomized or controlled studies in post-laser recovery, scars, hydration, wrinkles, and stretch-mark prevention (Review). The evidence is most useful when tied to the exact topical formula, because a standardized extract gel, an extract cream, and a multi-ingredient stretch-mark cream do not represent the same exposure (Review).
Key human study
Dose studied: 0.05% w/w ECa 233 gel
Population: 30 individuals with facial acne scars undergoing 2940 nm Er:YAG laser resurfacing
Duration: Gel applied four times daily for 7 days, then twice daily for 3 months
Researchers used a split-face randomized placebo-controlled design in which one side of the face received ECa 233, a standardized Centella asiatica extract, as a 0.05% w/w gel, where w/w means weight-by-weight, or the weight of extract relative to the total gel formulation (Research). The study reported improvement in post-laser erythema and wound appearance measures on the ECa 233 side, but the result applies specifically to this standardized gel in a post-laser setting (Research).
Result: Randomized human trial reported a statistically significant improvement
Evidence strength: Moderate
Study source: (Research)
Additional human study
Dose studied: 7% Centella asiatica extract cream
Population: 30 patients after split-thickness skin graft donor-site epithelialization
Duration: 12-week scar follow-up
A prospective randomized double-blind trial evaluated Centella cream for scar improvement after split-thickness skin graft donor-site healing (Research). Review summaries describe this study as using a 7% Centella asiatica extract cream, which means the cream contained Centella extract and does not mean the cream contained 7% pure asiaticoside, madecassoside, asiatic acid, or madecassic acid (Review).
Result: Randomized human trial reported a statistically significant improvement
Evidence strength: Moderate
Study source: (Research)
Cardiovascular Health
Human cardiovascular-related research on Centella asiatica mainly concerns venous microcirculation, venous hypertension, capillary filtration, and edema, rather than major cardiovascular events such as heart attack or stroke (Research). These studies generally used TTFCA, or total triterpenic fraction of Centella asiatica, so the mg dose refers to a concentrated triterpene fraction rather than dried herb powder (Research).
Key human study
Dose studied: 30 mg TTFCA three times daily or 60 mg TTFCA three times daily
Population: Patients with venous hypertension
Duration: Clinical trial duration reported in the study record
A human study evaluated TTFCA in venous hypertension using 90 mg/day and 180 mg/day dose arms (Research). Researchers reported improvements in capillary filtration and ankle edema, which supports a microcirculation-specific interpretation rather than a broad cardiovascular-disease claim (Research).
Result: Randomized human trial reported a statistically significant improvement
Evidence strength: Moderate
Study source: (Research)
Additional human study
Dose studied: 60 mg TTFCA three times daily
Population: Adults with mild to moderate superficial venous disease during medium- to long-distance flights
Duration: Flight-period exposure
A flight-edema study examined TTFCA 180 mg/day around medium- to long-distance flights in people with superficial venous disease (Research). The study addressed edema and microcirculatory changes linked to travel conditions, so the findings are best read as context-specific venous physiology evidence (Research).
Result: Human studies observed short-term physiological effects
Evidence strength: Limited
Study source: (Research)
Diabetes and Glycemic Control
Centella asiatica human research in diabetes is mostly about diabetic microangiopathy, edema, wound healing, and diabetic dry skin rather than direct glucose lowering (Research). The evidence includes oral TTFCA studies and oral/topical Centella studies in type 2 diabetes skin contexts, but formulations and outcomes differ across trials (Research).
Key human study
Dose studied: 60 mg TTFCA twice daily
Population: Patients with diabetic microangiopathy
Duration: 6 months
A clinical study evaluated 120 mg/day TTFCA in diabetic microangiopathy and reported improvements in microcirculatory parameters and capillary permeability markers (Research). This does not establish Centella as a glucose-control intervention, because the measured outcomes were microvascular rather than primary glycemic endpoints (Research).
Result: Human clinical study reported a modest improvement
Evidence strength: Moderate
Study source: (Research)
Additional human study
Dose studied: Oral and topical Centella asiatica exposure; formulation details differed by arm
Population: Controlled type 2 diabetes patients with dry skin
Duration: Clinical study duration reported in the trial publication
A three-arm randomized double-blind controlled trial studied oral and topical Centella asiatica in type 2 diabetes patients with dry skin (Research). The study reported improvements in dry skin condition and antioxidant-related measures, but the combined route design makes it difficult to attribute the result only to topical exposure or only to oral exposure (Research).
Result: Human clinical study reported a modest improvement
Evidence strength: Limited
Study source: (Research)
Cognitive Health
Human cognitive research on Centella asiatica includes post-stroke vascular cognitive impairment and systematic reviews of cognitive outcomes (Research). A systematic review and meta-analysis found that the overall evidence did not show strong, consistent cognitive improvement, although some acute mood and alertness measures were reported in specific studies (Review).
Key human study
Dose studied: 750 mg/day and 1000 mg/day Gotu kola extract
Population: Post-stroke vascular cognitive impairment
Duration: 6 weeks
A randomized study compared Gotu kola extract at 750 mg/day and 1000 mg/day with folic acid 3 mg/day in post-stroke vascular cognitive impairment (Research). The dose refers to extract mass, not fresh plant, dried herb, TTFCA, or topical extract percentage (Research).
Result: Human clinical studies reported mixed findings
Evidence strength: Limited
Study source: (Research)
Additional human study
Dose studied: Multiple Centella interventions across included studies
Population: Healthy adults and clinical populations in reviewed trials
Duration: Varied by study
A systematic review and meta-analysis evaluated Centella asiatica for cognitive function and mood across human studies (Review). The review concluded that the evidence did not demonstrate strong overall cognitive benefit, which makes the cognitive evidence more limited than the topical and microcirculatory evidence (Review).
Result: Human clinical studies reported mixed findings
Evidence strength: Mixed
Study source: (Review)
Mental Health
Human mental-health research on Centella asiatica includes acute anxiety physiology and small clinical contexts rather than large psychiatric trials (Research). Findings should be interpreted cautiously because some studies use short-term physiological measures rather than long-term clinical outcomes (Review).
Key human study
Dose studied: Single 12 g dose of crude Gotu kola herb
Population: Healthy adults
Duration: Acute single-dose study
A double-blind placebo-controlled study used a single 12 g crude Gotu kola dose and measured acoustic startle response as an acute anxiety-related physiological outcome (Research). The dose refers to crude herb material and should not be compared directly with mg-level TTFCA or standardized extract studies (Research).
Result: Human studies observed short-term physiological effects
Evidence strength: Emerging
Study source: (Research)
Additional human study
Dose studied: 500 mg twice daily hydro-ethanolic Centella asiatica extract
Population: Generalized anxiety disorder study population summarized in EMA assessment
Duration: 60 days
The European Medicines Agency assessment report summarizes a human study using 1000 mg/day of a 70% hydro-ethanolic Centella asiatica extract in generalized anxiety disorder (EMA). The study context is useful for documenting exposure, but broader human mental-health evidence remains limited and should not be presented as definitive psychiatric evidence (EMA).
Result: Human clinical study reported a modest improvement
Evidence strength: Limited
Study source: (EMA)
Pain and Acute Inflammation
Human pain-related research for Centella asiatica is preliminary and includes small pilot work rather than mature clinical evidence (Research). The evidence is exploratory because the available study was short, condition-specific, and not enough to generalize across pain conditions (Research).
Key human study
Dose studied: 250 mg ECa 233 twice daily or 500 mg ECa 233 twice daily
Population: Adults with acute temporomandibular disorder pain
Duration: 14 days
A randomized double-blind pilot trial tested oral ECa 233 at 500 mg/day and 1000 mg/day in acute temporomandibular disorder pain (Research). The 500 mg twice-daily group showed a short-term pain signal at day 7, but the pilot design means the result should be treated as preliminary rather than established pain evidence (Research).
Result: Human clinical study reported a modest improvement
Evidence strength: Emerging
Study source: (Research)
Dosage & Study Snapshot (Research Context)
Centella asiatica dosage evidence should be divided into topical application exposure and oral ingestion exposure, because a skincare percentage is not comparable to an oral capsule or extract dose (Research) (Research). In topical studies, exposure is described by concentration, vehicle, application frequency, treated area, and duration, while oral studies describe exposure as mg of TTFCA, mg of standardized extract, grams of crude herb, or grams of extract used for pharmacokinetic sampling (Research). TTFCA means total triterpenic fraction of Centella asiatica, TECA means titrated extract of Centella asiatica, and both terms describe triterpene-enriched Centella materials rather than ordinary dried leaf powder (EMA).
Topical application exposure bands
0.05% w/w ECa 233 gel:
A split-face randomized placebo-controlled post-laser study used 0.05% w/w ECa 233 gel, where ECa 233 means a standardized Centella asiatica extract and w/w means weight-by-weight, or the weight of extract compared with the total weight of the gel (Research). The gel was applied four times daily for 7 days and then twice daily for 3 months after Er:YAG laser resurfacing in people with facial acne scars (Research). The study reported improvements in erythema and wound appearance compared with placebo gel, making this one of the clearest human examples of a defined topical Centella extract concentration (Research). The 0.05% value describes the finished gel formula, not the exact amount of asiaticoside, madecassoside, asiatic acid, or madecassic acid that entered the skin (Research).
Result: Statistically significant improvement
Evidence strength: Moderate
Notes / limitations: This is a defined formulation concentration from one post-laser gel study, not a general cica percentage standard.
2.5–5% Centella asiatica extract cosmetic formulations:
A dermatology and cosmetology review describes human cosmetic testing of Centella asiatica extract formulations at 2.5% and 5% w/w, applied twice daily to forearm skin (Review). The review reports that the 5% formulation showed stronger moisturizing and anti-inflammatory effects than the lower concentration in that volunteer testing context (Review). These percentages refer to Centella extract incorporated into a topical formulation, not purified asiaticoside, madecassoside, asiatic acid, madecassic acid, or total triterpene percentage (Review). This evidence is useful for cosmetic-formulation context, but it is less clinically definitive than randomized scar or post-laser trials (Review).
Result: Preliminary signal
Evidence strength: Emerging
Notes / limitations: The study context helps explain cosmetic concentration ranges but does not identify how much active triterpene reached the skin.
7% Centella asiatica extract cream:
A split-thickness skin graft donor-site scar study evaluated Centella cream after epithelialization in a randomized double-blind design (Research). Review summaries describe this trial as using 7% Centella asiatica extract cream, meaning a cream containing Centella extract rather than 7% isolated madecassoside, asiaticoside, asiatic acid, or madecassic acid (Review). The study reported scar-score improvements over follow-up, but the result should be interpreted as evidence for that cream preparation in a post-surgical donor-site setting (Research). This percentage is useful for skincare readers because it shows that some clinical scar research used a higher extract-percentage cream than the 0.05% standardized gel study, but the two products are not equivalent (Research).
Result: Statistically significant improvement
Evidence strength: Moderate
Notes / limitations: The 7% value refers to extract in cream, not purified active-triterpene content.
Topical Centella-containing combination creams, concentration not isolated:
Pregnancy stretch-mark studies evaluated creams containing Centella asiatica extract together with alpha-tocopherol and collagen-elastin hydrolysates (Research) (Review). These studies reported fewer new stretch marks in treatment groups than placebo groups, but Centella’s independent contribution cannot be separated from the other ingredients in the formula (Review). For dosage interpretation, these studies are best classified as Centella-containing combination-formula evidence rather than Centella-only percent evidence (Research). These studies are relevant to real-world skincare products, but they do not define a standalone ideal Centella concentration (Review).
Result: Mixed findings
Evidence strength: Limited
Notes / limitations: Combination-product evidence is useful for formula context but weak for isolating Centella’s dose-response.
Oral ingestion exposure bands
90 mg/day TTFCA, as 30 mg three times daily:
A venous hypertension study used 30 mg TTFCA three times daily, equal to 90 mg/day of total triterpenic fraction of Centella asiatica (Research). This dose is not 90 mg of dried Gotu kola herb, because TTFCA refers to a concentrated triterpene fraction (Research). Researchers measured capillary filtration and edema-related outcomes in a venous hypertension context (Research). This dose band belongs to oral microcirculation research and should not be translated into topical skincare percentages (Research).
Result: Statistically significant improvement
Evidence strength: Moderate
Notes / limitations: The accessible study record does not provide enough information to convert this into whole-herb equivalents.
120 mg/day TTFCA, commonly 60 mg twice daily:
Diabetic microangiopathy studies used 60 mg TTFCA twice daily, equal to 120 mg/day of a triterpene fraction (Research). One 6-month study reported improvement in microcirculatory and capillary-permeability measures in diabetic microangiopathy (Research). A 12-month placebo-controlled study also examined TTFCA in diabetic microangiopathy and edema contexts (Research). These studies describe vascular and microvascular outcomes, not a direct glucose-lowering dose band (Research).
Result: Modest improvement
Evidence strength: Moderate
Notes / limitations: The dose is mg of triterpenic fraction, not mg of whole herb.
180 mg/day TTFCA, as 60 mg three times daily:
A flight-related edema study used 60 mg TTFCA three times daily, equal to 180 mg/day, in people with mild to moderate superficial venous disease during medium- to long-distance flights (Research). The study examined edema and microcirculatory changes linked to travel stress on the venous system (Research). This exposure is relevant to short-term venous physiology but should not be generalized to unrelated outcomes (Research). The material studied was TTFCA, so the dose is not interchangeable with crude herb grams or skincare percentages (Research).
Result: Preliminary signal
Evidence strength: Limited
Notes / limitations: The study context was travel-related venous edema rather than broad daily-use research.
500–1000 mg/day ECa 233 standardized extract:
A randomized pilot trial used oral ECa 233, a standardized Centella asiatica extract, at 250 mg twice daily and 500 mg twice daily, equal to 500 mg/day and 1000 mg/day, in acute temporomandibular disorder pain (Research). The mg dose describes extract mass rather than raw herb mass or TTFCA mass (Research). The 500 mg twice-daily group showed a short-term pain signal at 7 days, but the study was small and exploratory (Research). This dose band belongs in oral extract research, not topical cica skincare dosing (Research).
Result: Preliminary signal
Evidence strength: Emerging
Notes / limitations: The clinical domain was acute temporomandibular pain, and larger confirmation studies would be needed for stronger conclusions.
750–1000 mg/day Gotu kola extract:
A post-stroke vascular cognitive impairment trial studied Gotu kola extract at 750 mg/day and 1000 mg/day for cognitive outcomes (Research). The dose refers to extract mass rather than TTFCA, topical extract percentage, or crude herb weight (Research). The study compared the extract with folic acid, and the broader cognitive literature remains mixed according to systematic review evidence (Review). This band should be presented as cognitive-research context rather than a general oral dose recommendation (Research).
Result: Mixed findings
Evidence strength: Limited
Notes / limitations: The dose is extract mass, and it should not be converted into skincare or TTFCA exposure.
1000 mg/day hydro-ethanolic Centella asiatica extract:
The European Medicines Agency assessment report summarizes a study that used 500 mg twice daily of a 70% hydro-ethanolic Centella asiatica extract in a generalized anxiety disorder context (EMA). This exposure is extract mass, not whole herb mass, and it differs from TTFCA because the extraction method and constituent profile may differ (EMA). The evidence should be described cautiously because the broader human mental-health evidence is not mature (Review). This dose band is useful for documenting studied exposure, not for recommending use (EMA).
Result: Preliminary signal
Evidence strength: Limited
Notes / limitations: This is an oral extract study context and does not translate to skincare concentrations.
2–4 g single-dose standardized Centella asiatica water extract product:
A phase 1 pharmacokinetic study tested single 2 g and 4 g doses of a standardized Centella asiatica water extract product, abbreviated CAP, in healthy older adults (Research). Researchers measured pharmacokinetics, meaning how compounds appear and change over time in blood and urine, over a 12-hour sampling period (Research). For asiatic acid, the reported Cmax, or maximum plasma concentration, was 174 ng/mL after 2 g and 372 ng/mL after 4 g, and the reported Tmax, or time to maximum concentration, was 2.2 hours after 2 g and 2.8 hours after 4 g (Research). For madecassic acid, the reported Cmax was 107 ng/mL after 2 g and 197 ng/mL after 4 g, and the reported Tmax was 2.4 hours after 2 g and 2.7 hours after 4 g (Research).
Result: Human studies observed short-term physiological effects
Evidence strength: Emerging
Notes / limitations: This study measured absorption and blood/urine analytes, not clinical skin or vascular outcomes.
12 g single-dose crude Gotu kola herb:
A double-blind placebo-controlled acute study used a single 12 g crude Gotu kola herb dose in healthy adults (Research). This gram-level dose refers to crude herb material and is not equivalent to 12 g of extract or to mg-level TTFCA (Research). The study measured acoustic startle response as an anxiety-related physiological outcome after one exposure (Research). This is the clearest crude-herb exposure in the human evidence set, but it is acute and not directly comparable to standardized extract trials (Research).
Result: Preliminary signal
Evidence strength: Emerging
Notes / limitations: Crude herb grams and extract milligrams should not be converted without verified composition data.
Key Takeaways from Human Research
- Centella asiatica’s skin evidence is best described as formulation-specific: some human studies report defined topical concentrations, but those concentrations describe the finished formula rather than purified triterpene delivery into skin (Research) (Review).
- Topical research has reported signals for post-laser erythema, scar appearance, hydration, wrinkles, and stretch-mark prevention, but the evidence varies by formulation and study design (Review) (Research).
- Oral vascular studies mainly used TTFCA, so 90–180 mg/day refers to total triterpenic fraction of Centella asiatica rather than ordinary Gotu kola powder (Research).
- Diabetic microangiopathy studies reported microcirculatory changes with 120 mg/day TTFCA, but those findings do not establish Centella as a glucose-control intervention (Research).
- Human oral pharmacokinetic studies show that asiatic acid and madecassic acid can be measured in plasma after standardized Centella water extract, with Tmax values around 2.2–2.8 hours in one healthy older-adult study (Research).
Origin & Natural Occurrence
Centella asiatica is a plant species used in food and herbal traditions in several regions, but the human evidence in this article mainly concerns studied extracts, fractions, creams, and gels rather than ordinary dietary intake (EMA). The plant naturally contains triterpene glycosides and aglycones, including asiaticoside, madecassoside, asiatic acid, and madecassic acid (Review).
Centella ingredients used in supplements and skincare may come from dried plant material, water extracts, hydro-ethanolic extracts, standardized extracts, or triterpene-enriched fractions (EMA). Manufacturing origin matters because crude herb powder, standardized extract, TECA, TTFCA, and ECa 233 can contain different triterpene profiles and cannot be assumed equivalent (Research).
How It Behaves in the Body
Centella asiatica is not one single molecule; it is a plant source of multiple compounds, especially triterpene glycosides and aglycones, that may behave differently after topical or oral exposure (Review). A glycoside is a compound attached to a sugar group, such as asiaticoside or madecassoside, while an aglycone is the related non-sugar form, such as asiatic acid or madecassic acid (Review).
In oral pharmacokinetic research, single 2 g and 4 g doses of standardized Centella water extract produced measurable plasma profiles for the aglycones asiatic acid and madecassic acid in healthy older adults (Research). In the same study, the parent triterpene glycosides asiaticoside and madecassoside were not detected in plasma, and urinary excretion data showed limited detection for some parent compounds (Research).
The pharmacokinetic study reported dose-related increases in maximum plasma concentration for asiatic acid and madecassic acid after 2 g and 4 g CAP doses, with asiatic acid Cmax increasing from 174 ng/mL to 372 ng/mL and madecassic acid Cmax increasing from 107 ng/mL to 197 ng/mL (Research). The study also reported half-life values of 4.1 and 4.9 hours for asiatic acid after 2 g and 4 g, and 9.2 and 6.7 hours for madecassic acid after 2 g and 4 g (Research).
Mechanistic reviews describe possible Centella-related skin effects through collagen organization, wound-healing signaling, inflammation modulation, and extracellular-matrix remodeling, but many of these mechanisms come from experimental models rather than direct human mechanism studies (Review). The most evidence-anchored interpretation is that human claims should be tied to clinical studies of specific topical formulas or oral extracts, not to mechanisms alone (Review).
Absorption & Delivery Formats
Oral immediate-release: Oral studies have used TTFCA tablets, standardized extracts, hydro-ethanolic extracts, water extracts, and crude herb preparations (Research) (Research). The clearest modern human pharmacokinetic data in this evidence set come from single 2 g and 4 g doses of standardized Centella water extract, where blood and urine were sampled over 12 hours (Research).
Oral extended-release: The reviewed human evidence does not establish an extended-release Centella pharmacokinetic format (Research). Extended-release claims would need formulation-specific human data rather than extrapolation from immediate oral extract studies (Research).
Sublingual: The collected human evidence does not provide a clear sublingual Centella pharmacokinetic study (Research). Sublingual claims should therefore be treated as uncharacterized unless a specific human study is available (Research).
Topical: Topical studies include creams, gels, and combination scar or skincare products, with some studies reporting concentration and others reporting only product type or application schedule (Research) (Research). Topical concentration should be read as formulation percentage rather than systemic exposure or direct active-triterpene delivery (Research).
Injectable / IV: The collected human evidence does not establish Centella asiatica as an injectable or intravenous research format for this ingredient profile (EMA). The human evidence discussed here concerns oral and topical formats (EMA).
Quick Facts at a Glance
Onset, topical studies:
The post-laser ECa 233 study began topical application immediately after laser resurfacing, with 0.05% w/w gel applied four times daily for 7 days and then twice daily for 3 months (Research). This study design measured early post-procedure erythema and longer wound-appearance outcomes, but it does not define a universal onset time for all cica products (Research).
Tmax, oral pharmacokinetic study:
Tmax means time to maximum measured blood concentration, and in a healthy older-adult study of standardized Centella water extract, asiatic acid reached Tmax at 2.2 hours after 2 g and 2.8 hours after 4 g (Research). Madecassic acid reached Tmax at 2.4 hours after 2 g and 2.7 hours after 4 g in the same study (Research).
Cmax, oral pharmacokinetic study:
Cmax means maximum measured blood concentration, and the same study reported asiatic acid Cmax values of 174 ng/mL after 2 g and 372 ng/mL after 4 g standardized Centella water extract (Research). Madecassic acid Cmax values were 107 ng/mL after 2 g and 197 ng/mL after 4 g (Research).
Half-life:
Half-life means the estimated time for measured blood concentration to decrease by half, and the healthy older-adult study reported asiatic acid half-life values of 4.1 hours after 2 g and 4.9 hours after 4 g standardized Centella water extract (Research). Madecassic acid half-life values were 9.2 hours after 2 g and 6.7 hours after 4 g in the same study (Research).
Absorption routes studied:
Oral absorption has been studied through plasma and urine measurements after standardized Centella water extract, while topical studies usually measure local skin outcomes rather than systemic absorption (Research) (Research). These two evidence types answer different questions and should not be merged into one exposure model (Research).
Formulation differences:
TTFCA, TECA, ECa 233, crude Gotu kola herb, Centella extract cream, and Centella-containing combination products are not interchangeable materials (EMA). A milligram dose of TTFCA describes a triterpene fraction, while a topical percentage such as 0.05% w/w ECa 233 describes extract weight in a finished gel formulation (Research) (Research).
Variability drivers:
Variability may come from plant material, extraction solvent, standardization, triterpene profile, topical vehicle, treated skin condition, and clinical outcome being measured (Review). Human studies are difficult to compare when they use different Centella preparations and different endpoints (Review).
Tolerance / adaptation:
The collected human evidence does not establish a clear tolerance or adaptation pattern for Centella across oral and topical formats (Review). Repeated-use studies exist, but they were not designed primarily to test whether the body adapts to Centella over time (Research) (Research).
Evidence strength snapshot:
The strongest human evidence is in formulation-specific topical skin research and oral microcirculation studies (Research) (Research). Evidence for cognition, anxiety physiology, and pain is less mature because studies are smaller, more heterogeneous, or mixed across reviews (Review) (Research).
Safety, Interactions & Regulation
Centella asiatica safety depends on route, preparation, dose, skin condition, and population (EMA). Topical cosmetic safety has been reviewed by the Cosmetic Ingredient Review, which assessed Centella-derived cosmetic ingredients under reported cosmetic-use conditions (Review).
Single 2 g and 4 g doses of standardized Centella asiatica water extract were reported as well tolerated in a phase 1 pharmacokinetic study of healthy older adults (Research). Topical studies may still produce local reactions in some users, and the European Medicines Agency assessment discusses rash-related exclusions in topical contexts (EMA).
Interaction evidence is less developed than skin and microcirculation evidence in the collected human literature (Review). Population cautions should be route-specific because pregnancy stretch-mark studies are topical combination-product studies and should not be generalized to oral supplement safety in pregnancy (Research).
In the United States, dietary supplements are regulated as a category distinct from drugs, and FDA generally does not approve dietary supplements before they are marketed (FDA). U.S. dietary supplement structure/function claims may describe effects on normal structure or function but may not claim to diagnose, treat, cure, or prevent disease (FDA).
In the European context, the European Medicines Agency has published an assessment report on Centella asiatica herb that reviews traditional-use, human-study, topical-use, oral-use, and safety information (EMA). EU regulatory interpretation should be tied to the exact product category and jurisdiction rather than inferred from a general ingredient name (EMA).
Evidence Overview
Centella asiatica’s strongest human evidence is formulation-specific Beauty and Skin Health research and oral Cardiovascular Health microcirculation research, while Cognitive Health, Mental Health, and Pain and Acute Inflammation evidence is less consistent or more preliminary (Research) (Research) (Review). Human studies include topical randomized trials, oral venous and microcirculation trials, cognitive trials, acute physiological studies, and pharmacokinetic trials (Review). Confidence is not higher because the literature uses non-equivalent preparations, including TTFCA, TECA, ECa 233, hydro-ethanolic extract, water extract, crude herb, topical cream, topical gel, and multi-ingredient skincare formulas (EMA).
Topical evidence is clinically interesting but formulation-specific, because a 0.05% w/w ECa 233 gel, a 7% extract cream, and a Centella-containing stretch-mark cream are not interchangeable products (Research) (Research) (Research). The strongest topical conclusions are that certain studied Centella-containing or Centella-standardized topical preparations have been evaluated for post-laser redness, scar appearance, hydration, wrinkles, and stretch-mark prevention (Review). The evidence does not establish a universal cica percentage that applies across all skincare products (Review).
Oral evidence is also preparation-specific, especially in vascular studies that use TTFCA rather than ordinary herb powder (Research). The vascular and diabetic microangiopathy findings support microcirculation-related research interest, but they do not justify broad claims about cardiovascular disease treatment or diabetes control (Research).
The human pharmacokinetic literature helps explain oral exposure by showing measurable asiatic acid and madecassic acid after standardized water extract dosing, including reported Tmax and Cmax values after 2 g and 4 g CAP doses in healthy older adults (Research). Future research would strengthen confidence by reporting extract ratios, triterpene marker content, topical concentration, vehicle composition, treated area, and standardized clinical endpoints across larger trials (Review).
Evidence Confidence Classification
The overall human evidence for Centella asiatica is Moderate / Mixed because topical skin and oral microcirculation studies provide meaningful human evidence, while cognition, anxiety physiology, pain, and many formulation-dose questions remain limited or inconsistent (Review).
The strongest confidence belongs to formulation-specific topical skin research and oral microcirculation studies rather than broad ingredient-wide claims (Research) (Research). Evidence is mixed because Centella studies do not all use the same material, and mg of TTFCA, mg of extract, grams of crude herb, and topical percentage describe different exposure concepts (Research).
The evidence classification is not Strong because many trials are small, outcomes vary, and concentration or extract-ratio details are sometimes missing from study abstracts or product descriptions (Review). The evidence is stronger than purely Emerging because multiple human trials and reviews exist across skin and vascular domains (Review).
Similar Ingredients & Comparators
Similar supplement-style or skincare ingredients:
- Madecassoside
- Asiaticoside
- Asiatic acid
- Madecassic acid
- Aloe vera
- Panthenol
- Allantoin
- Hyaluronic acid
- Ceramides
- Niacinamide
- Vitamin E
Medical / pharma comparator categories:
- Topical scar-management products
- Silicone scar gels and sheets
- Topical barrier-repair agents
- Dermatologic post-procedure recovery products
- Venous microcirculation research agents
- Wound-care dressings
Combination Context
Centella asiatica + alpha-tocopherol + collagen-elastin hydrolysates:
This combination was studied in pregnancy stretch-mark prevention, where the formula contained Centella asiatica extract plus alpha-tocopherol and collagen-elastin hydrolysates (Research). The evidence is useful for combination-product context, but it cannot isolate Centella’s independent effect because multiple ingredients were used together (Review).
Centella asiatica + silicone gel + herbal oils/extracts:
Post-surgical scar studies have examined silicone gel plus herbal extracts including Centella-related components in scar-management contexts (Research) (Research). These studies are relevant to real-world scar products, but the contribution of Centella cannot be separated from silicone and the other formula components (Research).
Centella asiatica + ceramide:
A double-blind clinical trial in Indonesian batik workers compared Centella asiatica and ceramide creams for skin-barrier hydration measures (Research). The study supports the idea that Centella has been tested in barrier-care contexts, but it does not establish that Centella is superior to ceramide because both showed improvement in several measures (Research).
Oral + topical Centella asiatica:
A type 2 diabetes dry-skin study examined oral and topical Centella asiatica in a multi-arm design (Research). This design is useful for studying combined exposure, but it makes route-specific interpretation harder than a topical-only or oral-only trial (Research).
FAQ
What is Centella asiatica?
Centella asiatica is a plant-derived botanical ingredient also known as Cica, Gotu kola, Indian pennywort, and tiger grass (Review). It contains triterpene compounds, especially asiaticoside, madecassoside, asiatic acid, and madecassic acid (Review). It is studied both as a topical skincare ingredient and as an oral herbal or extract ingredient (Review).
What are the effective components in Gotu kola?
The most studied Centella asiatica components are asiaticoside, madecassoside, asiatic acid, and madecassic acid (Review). Asiaticoside and madecassoside are glycosides, meaning they include sugar groups, while asiatic acid and madecassic acid are aglycones, meaning they are related non-sugar forms (Review). In a human oral pharmacokinetic study, asiatic acid and madecassic acid were measurable in plasma after standardized Centella water extract, while asiaticoside and madecassoside were not detected in plasma (Research).
Why is Centella used as a skincare ingredient?
Centella is used as a skincare ingredient because human studies have examined Centella-containing topical formulations for post-procedure redness, scar appearance, hydration, wrinkles, and stretch-mark prevention (Research) (Review). The best-supported skincare interpretation is moderate but formulation-specific, meaning the evidence applies to studied products rather than every cica cream or serum (Research). Mechanistic reviews describe possible roles in wound-healing signaling, collagen organization, and inflammation modulation, but human claims should be tied to clinical formula studies rather than mechanism alone (Review).
What skin results have been observed in human studies?
Human topical studies have reported improvements in post-laser erythema, wound appearance, scar-related scores, hydration measures, wrinkle-related outcomes, or stretch-mark incidence depending on the formulation and study design (Research) (Review). These outcomes should be described separately because post-laser redness, scar remodeling, skin hydration, wrinkles, and stretch marks are different skin endpoints (Research). The evidence supports cautious formulation-specific statements, not a universal claim that Centella improves every skin concern (Review).
What topical concentrations have actually been studied?
Published human or human-relevant topical reports include 0.05% w/w ECa 233 gel, 2.5–5% Centella asiatica extract cosmetic formulations, and 7% Centella asiatica extract cream (Research) (Review). These percentages usually mean the weight of extract in the finished formulation, not the percentage of pure madecassoside, asiaticoside, total triterpenes, or active compound delivered through skin (Research) (Review). Many topical studies report product type and application frequency but do not clearly provide extract ratio, marker standardization, or exact triterpene content in the available study summary (Review).
What does 0.05% w/w ECa 233 mean in a skincare study?
0.05% w/w ECa 233 means the gel contained 0.05% standardized Centella asiatica extract by weight relative to the total weight of the gel (Research). It does not mean the gel contained 0.05% pure asiaticoside, madecassoside, asiatic acid, madecassic acid, or total triterpenes (Research). This distinction matters because skincare percentages usually describe the finished formulation, not the exact amount of active triterpene that reaches the skin (Review).
Why are topical Centella dosage studies hard to compare?
Topical Centella dosage studies are hard to compare because they use different materials, including standardized extract gels, extract creams, and multi-ingredient formulas (Research) (Research). A 0.05% w/w ECa 233 gel, a 7% Centella extract cream, and a stretch-mark cream containing Centella plus other ingredients do not represent the same exposure (Research) (Research). For skincare readers, the best-supported conclusion is that specific Centella formulations have been studied, while one ideal Centella percentage has not been established (Review).
What does human research study Centella asiatica for?
Human research studies Centella asiatica mainly for Beauty and Skin Health, Cardiovascular Health, Diabetes and Glycemic Control, Cognitive Health, Mental Health, and preliminary Pain and Acute Inflammation contexts (Review). Topical studies focus on scars, post-laser recovery, hydration, wrinkles, and stretch marks (Research) (Review). Oral studies focus more on venous microcirculation, diabetic microangiopathy, cognition, anxiety physiology, and pharmacokinetics (Research) (Research).
What are the best-supported human research areas?
The best-supported areas are topical skin research and oral microcirculation research, because multiple human studies exist in those domains (Research) (Research). Topical evidence includes post-laser gel, scar cream, hydration, wrinkle, and stretch-mark studies, but the results are formulation-specific (Research) (Review). Oral microcirculation evidence includes TTFCA studies in venous hypertension, edema, and diabetic microangiopathy (Research).
Where is the evidence mixed or limited?
The evidence is mixed or limited for cognition, anxiety physiology, and pain because studies are smaller, more heterogeneous, or not consistently positive across reviews (Review). Cognitive evidence includes a post-stroke vascular cognitive impairment trial, but systematic review evidence does not support strong overall cognitive conclusions (Research) (Review). Pain evidence is preliminary because the ECa 233 temporomandibular disorder trial was a short pilot study (Research).
How quickly does topical Centella act?
Topical onset depends on what is being measured, because erythema after laser treatment, skin hydration, scar maturation, and wrinkle appearance occur on different timelines (Research). In the post-laser ECa 233 study, the gel was applied four times daily for 7 days and then twice daily for 3 months, so early post-procedure and longer follow-up outcomes were both part of the protocol (Research). Scar and stretch-mark studies generally require weeks to months of follow-up because those outcomes involve tissue remodeling rather than a single immediate effect (Research).
What affects absorption and variability?
Absorption and variability depend on whether Centella is used orally or topically, and they also depend on extract type, triterpene profile, vehicle, and outcome measured (Research) (Review). Oral pharmacokinetic research shows measurable asiatic acid and madecassic acid after standardized water extract dosing, but those findings do not describe all oral extracts or topical products (Research). Topical variability depends on formulation concentration, base, skin condition, application amount, treated area, and study duration (Research).
Is tolerance reported?
The collected human evidence does not establish a clear tolerance or adaptation pattern for Centella asiatica across oral and topical use (Review). Some studies report repeated application or repeated oral dosing, but those designs were not primarily tolerance-adaptation studies (Research) (Research). Safety and tolerability should be interpreted by product type and population rather than assumed across all Centella preparations (EMA).
Why do studies disagree?
Studies can disagree because they use different Centella materials, such as TTFCA, TECA, ECa 233, hydro-ethanolic extract, water extract, crude herb, topical cream, or topical gel (EMA). They also measure different outcomes, including erythema, scar scores, hydration, capillary filtration, cognitive tests, startle response, and pain scores (Research) (Research). Differences in sample size, duration, concentration reporting, and standardization reduce cross-study comparability (Review).
What ingredients is Centella commonly combined with and why?
Centella has been studied in combination with alpha-tocopherol and collagen-elastin hydrolysates in pregnancy stretch-mark cream research (Research). It has also appeared in scar formulations with silicone gel and other herbal ingredients, where the goal was scar appearance rather than isolating Centella alone (Research) (Research). In barrier-focused skincare research, Centella has been compared with ceramide in occupational dry-skin contexts (Research).
What foods naturally contain Centella asiatica?
Centella asiatica itself is an edible plant in some traditional food and herbal contexts, but the article’s evidence base focuses on studied extracts, triterpene fractions, creams, and gels rather than dietary intake ranges (EMA). The collected human trials do not provide a strong ordinary-diet exposure ladder comparable to nutrients with food-intake databases (EMA). Therefore, dietary-food claims should be kept separate from supplement-style extract and topical skincare evidence (Research).
How is Centella asiatica regulated?
In the United States, Centella-containing dietary supplements fall under the dietary supplement regulatory framework, and FDA generally does not approve dietary supplements before marketing (FDA). U.S. supplement claims must not state that a product diagnoses, treats, cures, or prevents disease (FDA). In Europe, the European Medicines Agency has published an herbal assessment report for Centella asiatica herb, but regulatory interpretation still depends on product category, preparation, and jurisdiction (EMA).
Resources
- Centella asiatica herbal assessment report — European Medicines Agency — https://www.ema.europa.eu/en/documents/herbal-report/assessment-report-centella-asiatica-l-urb-herba-revision-1_en.pdf
- Dietary Supplements — U.S. Food and Drug Administration — https://www.fda.gov/food/dietary-supplements
- Structure/Function Claims — U.S. Food and Drug Administration — https://www.fda.gov/food/nutrition-food-labeling-and-critical-foods/structurefunction-claims
- Effects of ECa 233 gel after laser resurfacing — PubMed — https://pubmed.ncbi.nlm.nih.gov/32310680/
- Centella cream for scar improvement — PubMed — https://pubmed.ncbi.nlm.nih.gov/30310413/
- TTFCA in venous hypertension — PubMed — https://pubmed.ncbi.nlm.nih.gov/11666125/
- TTFCA in diabetic microangiopathy — PubMed — https://pubmed.ncbi.nlm.nih.gov/11666124/
- Centella pharmacokinetics in older adults — PubMed — https://pubmed.ncbi.nlm.nih.gov/35204098/
- Centella pharmacokinetic method and healthy older-adult study — Frontiers in Pharmacology — https://www.frontiersin.org/journals/pharmacology/articles/10.3389/fphar.2023.1228030/full
- Centella and cognitive function systematic review — PubMed — https://pubmed.ncbi.nlm.nih.gov/28878245/
- Centella in dermatology overview — PMC — https://pmc.ncbi.nlm.nih.gov/articles/PMC8627341/
- Centella in cosmetology — PMC — https://pmc.ncbi.nlm.nih.gov/articles/PMC3834700/
- Cosmetic Ingredient Review safety assessment — Cosmetic Ingredient Review — https://www.cir-safety.org/sites/default/files/centel062015FR.pdf
More from the Supplement Ingredients & Medical Ingredients Encyclopedia
