Centella asiatica is a botanical ingredient from the Apiaceae family whose human research has mainly examined topical skin repair, scar appearance, venous microcirculation, diabetic skin or microvascular contexts, cognition, anxiety physiology, and oral pharmacokinetics of triterpene compounds such as asiaticoside, madecassoside, asiatic acid, and madecassic acid (Review).
Centella asiatica is studied in two very different exposure contexts: topical application for skin, scars, hydration, wrinkles, and post-procedure recovery, and oral ingestion for microcirculation, cognitive outcomes, anxiety physiology, diabetic wound contexts, and pharmacokinetics (Review). The human evidence is strongest in topical dermatology and vascular/microcirculation research, but many trials are small, formulation-specific, or use products that are not directly interchangeable (Review). Topical concentration data exist for some studies, including 0.05% w/w ECa 233 gel, 2.5–5% Centella extract cosmetic formulations, and 7% Centella extract cream, but those percentages refer to the formulation used in the study and not necessarily to purified triterpene content or skin-delivered active dose (Research) (Review).
Ingredient Identity
- Official name(s): Centella asiatica (L.) Urb.
- Common names: Cica, Gotu kola, Indian pennywort, tiger grass.
- Classification: Botanical ingredient; triterpene-containing plant material and extract source (Review).
- Key studied constituents: Asiaticoside, madecassoside, asiatic acid, and madecassic acid are repeatedly described as major Centella triterpenes (Review).
- Endogenous vs exogenous: Centella asiatica is exogenous; it is a plant-derived ingredient rather than a compound normally produced by the human body (EMA).
- Common research formats: Topical creams, gels, scar formulations, oral triterpene fractions, standardized extracts, crude herb preparations, and pharmacokinetic extract studies (Review).
Ingredient Snapshot
- Classification: Centella asiatica is a triterpene-rich botanical used in topical and oral human research (Review).
- Endogenous vs exogenous status: It is an exogenous plant ingredient and is not 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-related contexts (Review).
- Common study formats: Topical studies use creams or gels, while oral studies use TTFCA-style triterpene fractions, standardized extracts, or crude herb preparations (Research) (Research).
- Pharmacokinetic characterization status: Human pharmacokinetic work exists for standardized oral Centella water extract, with asiatic acid and madecassic acid detected as measurable plasma analytes after single 2 g and 4 g doses (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: EMA has reviewed Centella asiatica herb in an herbal-medicine assessment context, including oral and topical use, safety, and traditional-use considerations (EMA).
- Evidence maturity: The overall evidence is moderate for several topical and vascular research areas, but limited or emerging for cognition, anxiety physiology, and pain contexts because study sizes and formulations vary (Review).
Introduction
Centella asiatica is a creeping herbaceous plant whose extracts contain pentacyclic triterpenes, especially asiaticoside, madecassoside, asiatic acid, and madecassic acid (Review). In skincare, “cica” usually refers to Centella-derived extracts or isolated Centella triterpenes used in creams, gels, moisturizers, or post-procedure products (Review).
People look up Centella asiatica because it appears in both supplement and skincare contexts, but the human evidence differs substantially by route and formulation (Review). Human research has studied topical Centella for scars, wound appearance, post-laser recovery, hydration, wrinkles, and stretch-mark prevention, while oral studies have examined venous microcirculation, diabetic microangiopathy, diabetic wound healing, cognition, anxiety physiology, pain, and pharmacokinetics (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 these two routes should not be interpreted as equivalent exposures (Review).
- Topical Centella research includes scar, post-laser, hydration, wrinkle, and stretch-mark studies, but many results are tied to specific creams, gels, or combination products (Research) (Review).
- Oral Centella studies often use TTFCA, standardized extracts, or crude herb, and mg amounts mean different things depending on whether the material is a triterpene fraction, extract, or whole herb (Research) (Research).
- The most developed oral research area is venous and microcirculatory function, where TTFCA has been studied in venous hypertension, edema, and diabetic microangiopathy (Research).
- Topical concentration data are available in some studies, including 0.05% w/w ECa 233 gel, 2.5–5% cosmetic Centella extract formulations, and 7% Centella extract cream, but these percentages do not automatically describe pure active triterpene concentration (Research) (Review).
- Human evidence for cognition and anxiety physiology exists, but systematic review evidence does not show strong, consistent cognitive effects across studies (Review).
- Safety interpretation depends on route, formulation, and population, and regulatory claims should distinguish dietary supplements, cosmetics, and herbal medicinal assessments (FDA) (EMA).
Human Research Findings by Condition
Beauty and Skin Health
Human skin research on Centella asiatica includes randomized and controlled studies in scars, post-laser healing, dry skin, wrinkles, and pregnancy-related stretch marks (Review). The evidence is most useful when interpreted by exact formulation because topical Centella studies often use creams, gels, or combination products rather than a single universal ingredient concentration (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 0.05% w/w ECa 233 gel and the other side received placebo gel after laser resurfacing (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 topical gel and procedure context (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). The full-study context is commonly summarized as a 7% Centella asiatica extract cream, meaning a percent of extract in the cream base rather than a percent of pure asiaticoside, madecassoside, or total triterpenes (Review).
Result: Randomized human trial reported a statistically significant improvement
Evidence strength: Moderate
Study source: (Research)
Cardiovascular Health
Human cardiovascular-related research for Centella asiatica mainly concerns venous microcirculation, venous hypertension, capillary filtration, and edema rather than major cardiovascular events (Research). These studies generally used TTFCA, meaning 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: Study duration reported in the clinical trial 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 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 vascular 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 diabetes treatment, 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 varied by study 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 to topical exposure alone or oral exposure alone (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, or TTFCA, and the extract ratio should not be assumed unless a specific source states it clearly (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
EMA’s 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 the article should avoid presenting it as definitive psychiatric efficacy evidence because the broader human evidence remains limited (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 best-fitting interpretation 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 signal at day 7, but the study’s 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 must be separated into topical application and oral ingestion because a skincare percentage is not comparable to an oral capsule dose (Research) (Research). In topical studies, exposure is usually defined by concentration, application frequency, vehicle, surface area, and duration, while oral studies define exposure as mg of TTFCA, mg of standardized extract, grams of crude herb, or grams of extract used for pharmacokinetics (Research). “TTFCA” means total triterpenic fraction of Centella asiatica, “TECA” means titrated extract of Centella asiatica, and both terms describe triterpene-enriched 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 the percentage means the weight of the standardized extract in the gel formulation rather than a direct measure of triterpene delivered through skin (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, but the findings are specific to ECa 233 gel and post-procedure skin recovery (Research). This concentration is useful for skincare readers because it is one of the clearest published topical percentage examples in human research (Research).
Result: Statistically significant improvement
Evidence strength: Moderate
Notes / limitations: The 0.05% value is a formulation concentration, not a universal Centella skincare dose.
2.5–5% Centella asiatica extract cosmetic formulations:
A dermatology/cosmetology review describes in vivo cosmetic testing of Centella asiatica extract formulations at 2.5% and 5% w/w applied twice daily to human 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 and should not be interpreted as purified asiaticoside, madecassoside, or total triterpene concentration (Review). This evidence is relevant to 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 review supports formulation-level concentration context, but the active triterpene dose delivered to skin is not established.
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). Topical review summaries describe this study as using 7% Centella asiatica extract cream, meaning a cream containing Centella extract rather than 7% isolated madecassoside or asiaticoside (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 relevant to skincare-dose questions because it shows that some clinical scar studies used higher extract percentages than the 0.05% ECa 233 gel study, but the materials are not equivalent (Review).
Result: Statistically significant improvement
Evidence strength: Moderate
Notes / limitations: The percentage refers to extract in cream and does not identify exact triterpene-marker delivery into skin.
Topical Centella-containing combination creams, concentration not always 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 clean percent-based Centella monotherapy evidence (Research). The concentration question remains partly unresolved because not all accessible abstracts provide exact Centella extract percentage, extract ratio, or triterpene standardization (Review).
Result: Mixed findings
Evidence strength: Limited
Notes / limitations: Combination-product studies are useful for real-world skincare context but weak for identifying an exact Centella-only concentration.
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, which equals 90 mg/day of total triterpenic fraction of Centella asiatica (Research). This dose is not 90 mg of dried Gotu kola herb and should not be compared with crude herb gram doses (Research). Researchers measured capillary filtration and edema-related outcomes in a venous hypertension context (Research). The study supports a vascular microcirculation interpretation rather than a general wellness or skincare-dose interpretation (Research).
Result: Statistically significant improvement
Evidence strength: Moderate
Notes / limitations: Extract ratio is not clearly available from the accessible citation record.
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 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 or skincare percentages (Research).
Result: Preliminary signal
Evidence strength: Limited
Notes / limitations: The study context was travel-related venous edema, not routine daily supplementation.
500–1000 mg/day ECa 233 standardized extract:
A randomized pilot trial used oral ECa 233 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). ECa 233 is a standardized Centella extract, so the mg dose describes extract mass rather than raw herb 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 confirmation in larger studies is needed.
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: Extract ratio and marker standardization should not be assumed unless stated by the study.
1000 mg/day hydro-ethanolic Centella asiatica extract:
EMA 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:
A phase 1 pharmacokinetic trial tested single 2 g and 4 g doses of standardized Centella asiatica water extract in healthy older adults (Research). Researchers detected asiatic acid and madecassic acid in plasma, while parent glycosides were not detected in plasma or were minimal in urine (Research). A related bioanalytical study validated HPLC-MS/MS measurement of Centella triterpenes in human plasma and urine for this research context (Research). This band is pharmacokinetic exposure, not clinical efficacy dosing (Research).
Result: Human studies observed short-term physiological effects
Evidence strength: Emerging
Notes / limitations: PK doses help explain absorption and metabolism but do not define supplement or skincare dosing.
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 validated composition data.
Key Takeaways from Human Research
- Topical Centella evidence is formulation-specific, and the clearest percent-based human examples include 0.05% w/w ECa 233 gel, 2.5–5% cosmetic extract formulations, and 7% extract cream (Research) (Review).
- Oral vascular studies mainly used TTFCA, so 90–180 mg/day refers to a triterpene fraction rather than whole herb powder (Research).
- Diabetic microangiopathy studies reported microcirculatory changes with 120 mg/day TTFCA, but they should not be interpreted as direct diabetes-treatment evidence (Research).
- Cognitive and mental-health evidence is less mature than topical and microcirculatory evidence, with systematic review findings described as mixed or limited (Review).
- Pharmacokinetic studies show measurable human exposure to asiatic acid and madecassic acid after oral standardized extract, but PK findings do not establish clinical outcomes by themselves (Research).
Origin & Natural Occurrence
Centella asiatica is a plant species traditionally used in Asian herbal systems and is botanically distinct from endogenous human compounds (EMA). It 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, hydro-ethanolic extracts, water extracts, standardized extracts, or triterpene-enriched fractions (EMA). Manufacturing origin matters because a crude herb powder, a 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 chemical; it is a plant source of multiple triterpenes that may behave differently after topical or oral exposure (Review). In plain terms, topical products are studied for local skin effects, while oral studies examine whether Centella-derived compounds or metabolites appear in circulation and influence measurable physiological outcomes (Research).
Human pharmacokinetic research suggests that after oral standardized Centella water extract, asiatic acid and madecassic acid are measurable in plasma, while parent glycosides such as asiaticoside and madecassoside are not detected in plasma or are limited in urine (Research). This pattern suggests that oral Centella glycosides may be transformed before or during absorption, although the clinical meaning of those blood measurements remains separate from efficacy claims (Research).
Mechanistic reviews describe 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). For readers, the simplest interpretation is that human evidence is strongest when a clinical study directly tested a topical formula or oral extract and measured a practical outcome, not when a mechanism is inferred from laboratory work (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 human PK evidence is most clearly described for standardized water extract at 2 g and 4 g single doses (Research).
Oral extended-release: The reviewed human evidence does not clearly establish an extended-release Centella pharmacokinetic format (Research). Claims about extended-release behavior should not be made without formulation-specific human data (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).
Transdermal / topical: Topical studies include creams, gels, and combination scar or skincare products, with some human 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 (Research).
Injectable / IV: The collected human evidence does not establish Centella asiatica as an injectable or IV research format for the article’s scope (EMA). The evidence base discussed here concerns oral and topical formats (EMA).
Quick Facts at a Glance
Onset reported: Topical post-laser studies measured early erythema and wound appearance after repeated application beginning immediately after laser treatment, while oral acute anxiety physiology was measured after a single crude-herb dose (Research) (Research). Onset depends heavily on outcome type, so scar remodeling, hydration, acute physiology, and PK exposure should not be grouped into one onset estimate (Research).
Time to peak (Tmax): Human PK studies measured Centella triterpene analytes after single 2 g and 4 g standardized water extract doses, but the practical Tmax differs by analyte and study method (Research). The most reliable article wording is that asiatic acid and madecassic acid were measurable after dosing rather than giving a universal Tmax for all Centella products (Research).
Half-life (t½): Half-life data are formulation- and analyte-specific, and the available PK work should not be generalized to all Centella powders, extracts, or skincare products (Research). The most defensible statement is that human PK characterization exists for selected standardized oral extract conditions (Research).
Typical duration: Human topical studies range from short post-procedure protocols to multi-week or multi-month follow-up, while oral studies range from single-dose acute designs to 6- or 12-month microcirculation studies (Research) (Research). Duration should be interpreted by condition and outcome rather than as one ingredient-wide timeline (Research).
Absorption routes studied: Oral absorption has been studied using plasma and urine triterpene measurements, while topical studies generally focus on local skin outcomes rather than systemic absorption (Research) (Research). These two routes answer different questions and should not be merged into a single exposure model (Research).
Formulation differences: TTFCA, TECA, ECa 233, hydro-ethanolic extract, water extract, crude herb, and topical creams can represent materially different exposures (EMA). This is why the article distinguishes extract mass, triterpene fraction mass, crude herb grams, and topical formulation percentages (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 evidence does not establish a clear human tolerance or adaptation pattern for Centella across oral and topical formats (Review). Any tolerance claim would need formulation-specific repeated-use evidence and should not be inferred from short trials alone (Review).
Evidence strength snapshot: Human evidence is strongest for formulation-specific topical skin research and vascular microcirculation studies, while cognition, anxiety physiology, and pain evidence remains limited or emerging (Review) (Research). Overall confidence is limited by small sample sizes, heterogeneous formulations, and inconsistent standardization details (Review).
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 EMA’s assessment discusses rash-related exclusions in topical contexts (EMA).
Interaction evidence is not as well developed as the 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, EMA 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
The overall human evidence for Centella asiatica is strongest in Beauty and Skin Health and Cardiovascular Health, where topical studies and oral TTFCA microcirculation trials provide the most developed human data (Research) (Research). Evidence is more limited in Cognitive Health, Mental Health, and Pain and Acute Inflammation, where trials are smaller, outcomes differ, or systematic review findings are mixed (Review) (Research). Confidence is not higher because Centella studies use non-equivalent preparations such as TTFCA, ECa 233, hydro-ethanolic extract, crude herb, topical cream, and topical gel (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). The strongest topical conclusions are therefore not “Centella at any concentration improves skin,” but rather that certain Centella-containing or Centella-standardized topical preparations have been studied for scars, post-laser recovery, hydration, wrinkles, and stretch-mark prevention (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 (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 vascular microcirculation studies provide meaningful human data while cognition, anxiety physiology, pain, and many formulation-dose questions remain limited or inconsistent (Review).
The strongest confidence belongs to formulation-specific topical and oral microcirculation contexts rather than to broad ingredient-wide benefit 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 all 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 accessible reports (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, and Indian pennywort (Review). It contains triterpenes such as 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 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 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, especially 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 frequently during the first 7 days and then twice daily for 3 months, so early and longer-term 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 immediate surface hydration (Research).
What topical concentrations have actually been studied?
Some human and 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 accessible citation record (Review).
Why do topical dosage studies often feel unclear for skincare readers?
Topical Centella studies often test complete formulations, so “dose” may mean concentration, vehicle, frequency, treated area, and duration rather than a single active ingredient amount (Research). A 0.05% ECa 233 gel, a 7% extract cream, and a Centella-containing stretch-mark cream are not directly comparable because the extract type and co-ingredients differ (Research) (Research). For skincare interpretation, the most accurate wording is that available concentration data describe studied formulations, not a universal optimal Centella percentage (Review).
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 PK 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, 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, EMA 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 — EMA — https://www.ema.europa.eu/en/documents/herbal-report/assessment-report-centella-asiatica-l-urb-herba-revision-1_en.pdf
- Dietary Supplements — FDA — https://www.fda.gov/food/dietary-supplements
- Structure/Function Claims — FDA — 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 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 — CIR — https://www.cir-safety.org/sites/default/files/centel062015FR.pdf
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