Supplements

Bacopa Monnieri

Updated · 27 sources · Editorial policy

Bacopa monnieri is a creeping wetland herb native to the Indian subcontinent. In Ayurvedic medicine it is called Brahmi, and it has been used for centuries for memory, anxiety and epilepsy. Today it is sold worldwide as an herbal supplement for memory and focus, usually as an extract standardized to its saponins, the bacosides (LiverTox).

Bacopa and ginkgo are among the most studied herbal “nootropics” (Tiemtad et al., Phytomedicine 2026). Several 12-week randomized trials in healthy adults found small improvements in memory recall, but others, including a 2025 trial, found no cognitive benefit. Bacopa is not approved as a treatment for any medical condition in the US, and no human pharmacokinetic data (such as a half-life) have been published.

This page summarizes what randomized trials, systematic reviews and the NIH LiverTox database report. It is for education only and is not medical advice.

Property Detail
Type Herbal extract sold as a dietary supplement
Other names Brahmi (a name also used for gotu kola), water hyssop
Main active constituents Triterpenoid saponins called bacosides (bacoside A is a mixture of four saponins)
Route Oral (capsules or tablets of extract)
Doses in trials Mostly 300–450 mg/day of standardized extract for 12 weeks; LiverTox lists 300–600 mg/day as typical
Time course in trials Effects seen at 12 weeks, not at 5 weeks
Half-life Not established; no human pharmacokinetic data published
Liver safety LiverTox likelihood score E (unlikely cause of liver injury)
US status Not FDA-approved for any condition; sold over the counter
WADA status Not named on the 2026 Prohibited List

What it is

The supplement is made from the leaves and other aerial parts of the plant. LiverTox notes that the plant contains more than 100 components, including flavonoids, saponins, triterpenoids, sterols and lipids (LiverTox). The memory effects are usually attributed to the saponins (soap-like plant glycosides).

The naming of these saponins is messy. Older papers credited “bacosides A and B.” HPLC analysis later showed that “bacoside A” is a mixture of four saponins: bacoside A3, bacopaside II, bacopasaponin C and a jujubogenin isomer of bacopasaponin C (Deepak et al., Phytochem Anal 2005). In plant samples from different regions of India, each of these made up well under 1% of the dried herb by weight:

Saponin Content in Indian plant samples (% w/w)
Bacoside A3 0.14–0.85
Bacopaside II 0.12–0.69
Jujubogenin isomer of bacopasaponin C 0.05–0.72
Bacopasaponin C 0.05–0.44

Because the raw herb contains so little saponin, commercial products are concentrated extracts. For example, the extract used in one US trial was a 50:1 extract with at least 50% bacosides A and B. Each 300 mg tablet was equivalent to about 15 g of herb and 150 mg of bacosides (Calabrese et al., J Altern Complement Med 2008). Branded extracts used in trials include KeenMind (CDRI 08), BacoMind and Bacumen. They differ in how they are made and standardized, so results from one extract may not apply to another.

Proposed mechanisms

Almost all mechanism data come from animal and cell-culture studies. A 2013 review listed the main proposed mechanisms (Aguiar and Borowski, Rejuvenation Res 2013):

  • antioxidant protection of nerve cells;
  • inhibition of acetylcholinesterase (the enzyme that breaks down the memory-related neurotransmitter acetylcholine) and/or activation of the enzyme that makes it;
  • reduced β-amyloid (the protein that builds up in Alzheimer disease) in animal models;
  • increased cerebral blood flow;
  • modulation of acetylcholine, serotonin and dopamine signaling.

None of these mechanisms has been confirmed as the cause of the effects seen in human trials.

Pharmacokinetics

As of 2008, a trial report noted that “there are no data currently available on the pharmacokinetics of Bacopa or its saponins” (Calabrese et al., 2008). We found no published human study since then that reports a half-life, peak level or bioavailability for bacopa saponins.

What does exist is limited:

Regulatory status

In the US, bacopa is sold as a dietary supplement. LiverTox states that it “is not approved in the United States as therapy of any medical condition” and that it has not been shown effective for any disease in adequately controlled trials (LiverTox).

Bacopa is not named on the WADA 2026 Prohibited List.

What the research shows

Memory in healthy adults: individual trials

Most trials gave 300–450 mg/day of a standardized extract for 12 weeks. Results are mixed, and the positive findings were usually on some, not all, memory tests.

Trial Participants Extract and dose Duration Main result
Stough 2001 46 healthy adults, 18–60 years KeenMind 300 mg/day 12 weeks Faster visual information processing, better learning rate and memory consolidation, lower state anxiety
Roodenrys 2002 76 adults, 40–65 years Brahmi extract 3 months Better retention of new information (slower forgetting); no effect on attention, short-term memory or anxiety
Stough 2008 107 enrolled, 62 completed KeenMind 2 × 150 mg/day 90 days Better spatial working memory accuracy; fewer false alarms on a vigilance task
Calabrese 2008 54 adults 65 or older (mean 73.5); 48 completed Standardized extract 300 mg/day 12 weeks Better delayed word recall (primary outcome) and Stroop scores; no effect on divided attention or working memory
Morgan 2010 98 adults over 55; 81 completed BacoMind 300 mg/day 12 weeks Better verbal learning and delayed recall; more gastrointestinal side effects
Sathyanarayanan 2013 72 adults, 35–60 years Extract 450 mg/day 12 weeks No significant difference on any cognitive measure; trend toward lower state anxiety
Lopresti 2025 101 adults 40–70 with self-reported memory problems; 87 completed Bacumen 300 mg/day 12 weeks No difference in verbal learning, attention or working memory; lower self-reported stress reactivity (secondary outcome)

The trials published from 2001 to 2010 each reported a benefit on at least one memory measure. The two most recent trials, an Indian trial at 450 mg/day and a 2025 Australian trial at 300 mg/day, found no cognitive benefit on their main outcomes.

Memory in healthy adults: pooled analyses

Review Trials included Main finding
Pase et al., 2012 (systematic review) 6 RCTs, all 12 weeks, 300–450 mg/day of three different extracts Improvement on 9 of 17 tests of free recall memory; little evidence of benefit in other cognitive areas
Kongkeaw et al., 2014 (meta-analysis) 9 RCTs, 518 participants, 12 weeks or longer Trail Making Test B shortened by 17.9 ms (95% CI −24.6 to −11.2); choice reaction time −10.6 ms (95% CI −12.1 to −9.2)
Tiemtad et al., 2026 (network meta-analysis) 29 RCTs of bacopa or ginkgo, 2,107 healthy adults At 600 mg/day or more, bacopa improved working memory vs placebo (SMD 2.03, 95% CI 1.28–2.78); no difference in attention or processing speed

The Kongkeaw meta-analysis concluded that bacopa may improve speed of attention, but that only a large head-to-head trial against an existing medicine would give definitive answers. The 2026 network meta-analysis compared bacopa doses with each other and with ginkgo mostly through indirect comparisons, and its authors note that the lack of direct comparisons limits the strength of the evidence. An SMD (standardized mean difference) expresses the effect in units of standard deviation, which allows results from different tests to be pooled.

Alzheimer disease and mild cognitive impairment

A 2022 systematic review found only 5 eligible randomized trials in people with Alzheimer disease or mild cognitive impairment due to Alzheimer disease (Basheer et al., Interact J Med Res 2022):

  • 3 of the 5 trials used bacopa combined with other herbs;
  • doses ranged from 125 mg to 500 mg twice daily;
  • all 5 trials were judged at high risk of bias;
  • the authors found no difference between bacopa and placebo or donepezil, based on very low certainty evidence.

The largest direct comparison planned 48 patients on bacopa 300 mg/day vs donepezil 10 mg/day for 12 months. It stopped after recruiting 34 because of slow recruitment and dropouts, and found no difference in the rate of change on the main cognitive scale (ADAS-Cog) (Prabhakar et al., Ann Indian Acad Neurol 2020).

Children and attention

A 2016 systematic review found 5 studies in children and adolescents, with small to medium effects on language and memory measures (mean d = 0.42). Mild side effects were reported by 2.3% of participants (Kean et al., Complement Ther Med 2016). The authors called for replicated designs with stricter statistics.

The same group then ran a 14-week randomized, placebo-controlled trial of CDRI 08 in 112 boys aged 6–14 with inattention and hyperactivity (93 analyzed). It found no difference in behavior, the main target, with some secondary improvements in cognitive flexibility, executive function and sleep routine (Kean et al., Phytother Res 2022).

Anxiety and stress

Anxiety and stress were secondary outcomes in most trials, and results are inconsistent:

  • lower state anxiety in Stough 2001;
  • no effect on anxiety in Roodenrys 2002;
  • lower combined anxiety and depression scores over time in older adults in Calabrese 2008;
  • only a non-significant trend in Sathyanarayanan 2013;
  • lower self-reported stress reactivity and fatigue after a demanding task in Lopresti 2025.

No trial has shown bacopa to be an effective treatment for an anxiety disorder.

Side effects and risks

Common side effects

Side effects in trials have been mostly gastrointestinal:

  • Morgan 2010 (300 mg/day): increased stool frequency, abdominal cramps and nausea, more often than with placebo (Morgan and Stevens, 2010).
  • Lopresti 2025 (300 mg/day): more self-reported adverse reactions than placebo (p = 0.024), mainly digestive complaints and headaches; no serious reactions (Lopresti and Smith, 2025).
  • Calabrese 2008 (300 mg/day): 18 adverse events on bacopa vs 23 on placebo, with no difference between groups; digestive problems and flu-like symptoms were the most common possibly related events (Calabrese et al., 2008).
  • Phase I study: 23 healthy volunteers took BacoMind 300 mg/day for 15 days, then 450 mg/day for 15 days. Blood counts, blood chemistry and ECGs showed no untoward changes; mild gastrointestinal events resolved on their own (Pravina et al., Phytomedicine 2007).

LiverTox also lists dry mouth, dizziness, insomnia, flatulence and rash as reported minor effects (LiverTox). Long-term toxicity studies in humans have not been done (Aguiar and Borowski, 2013).

Liver

LiverTox gives bacopa a likelihood score of E, meaning it is an unlikely cause of clinically apparent liver injury. Bacopa has not been linked to liver enzyme rises in trials or to cases of liver injury in US and Spanish liver-injury registries. In one published case of severe liver injury after a four-herb Ayurvedic regimen that included Brahmi, the causality assessment pointed to a different herb (LiverTox). Few trials have reported liver tests, so the data are reassuring but not extensive.

Drug interactions

  • Cytochrome P450 enzymes (in vitro). In human recombinant enzyme assays, bacopa extract inhibited CYP2C19, CYP2C9, CYP1A2 and CYP3A4, the liver and gut enzymes that clear many prescription drugs. The isolated bacosides had negligible effect, which suggests other constituents are responsible (Ramasamy et al., Molecules 2014). Whether this causes interactions in people has not been tested in clinical studies.
  • Case report. A 58-year-old woman taking cevimeline (a muscarinic drug for Sjögren syndrome) developed sweating, nausea, malaise and a fast heart rate after taking a bacopa and phosphatidylserine supplement. Symptoms resolved after stopping the supplement (Acquarulo et al., J Med Case Rep 2022). A single case cannot prove cause.

Thyroid and fertility (animal data)

Two rodent studies raise questions that have not been studied in people:

  • Thyroid, in mice: bacopa extract at 200 mg/kg raised T4 (thyroxine) by 41% (Kar et al., J Ethnopharmacol 2002). A 2025 review lists hyperthyroidism as a condition in which bacopa should be used with caution (Gościniak et al., Nutrients 2025).
  • Male fertility, in mice: 250 mg/kg/day for 28 or 56 days reduced sperm count, motility and viability and suppressed fertility. Serum testosterone and libido were unaffected, and all changes reversed within 56 days of stopping (Singh and Singh, Contraception 2009).

Who has no safety data

Safety in pregnancy and breastfeeding has not been established (Gościniak et al., 2025).

Quality and contamination

Product quality is a real issue for bacopa:

  • Name confusion. “Brahmi” is also used for gotu kola (Centella asiatica), a different plant (LiverTox).
  • Inconsistent standardization. Many products are still labeled by “bacosides A and B” content, although the identity of “bacoside B” remains disputed (Deepak and Amit, Fitoterapia 2013). Extracts used in trials differ in solvent, ratio and saponin content.
  • Heavy metals and pesticides. An Indian study tested 12 Ayurvedic Brahmi formulations from 6 manufacturers. Lead, cadmium, chromium and nickel were found in all samples but below permissible limits. Several pesticide residues, including DDT and hexachlorocyclohexane isomers, were detected in some samples (Mishra et al., J Integr Med 2016).

Key takeaways

  • An Ayurvedic herb with a real trial record. Systematic reviews pool 6–9 randomized trials of 12 weeks or longer in healthy adults, mostly at 300–450 mg/day of standardized extract.
  • Memory effects are small and inconsistent. Pooled analyses suggest benefits on free recall and attention speed, but the two most recent trials, at 300 and 450 mg/day, found no cognitive benefit on their main outcomes.
  • Effects, if any, take weeks. Trials showed changes at 12 weeks rather than at 5 weeks; no human half-life or other pharmacokinetic data have been published.
  • No proven medical use. Evidence in Alzheimer disease is very low certainty, and a trial in boys with hyperactivity found no behavioral benefit.
  • Generally well tolerated. Gastrointestinal upset is the most common side effect, and LiverTox rates it an unlikely cause of liver injury. In vitro CYP inhibition, and thyroid and sperm effects in mice, remain untested in people.

Sources

  1. National Institute of Diabetes and Digestive and Kidney Diseases. LiverTox: Bacopa. Updated April 24, 2024. NCBI Bookshelf.
  2. Deepak M, Sangli GK, Arun PC, et al. Quantitative determination of the major saponin mixture bacoside A in Bacopa monnieri by HPLC. Phytochem Anal. 2005;16(1):24–29. PubMed.
  3. Deepak M, Amit A. ‘Bacoside B’–the need remains for establishing identity. Fitoterapia. 2013;87:7–10. PubMed.
  4. Aguiar S, Borowski T. Neuropharmacological review of the nootropic herb Bacopa monnieri. Rejuvenation Res. 2013;16(4):313–326. PubMed.
  5. Bhateria M, Ramakrishna R, Puttrevu SK, et al. Analysis of bacopaside I in biomatrices using liquid chromatography-tandem mass spectrometry: Pharmacokinetics and brain distribution in Swiss-albino mice. J Pharm Biomed Anal. 2016;125:101–109. PubMed.
  6. Stough C, Lloyd J, Clarke J, et al. The chronic effects of an extract of Bacopa monniera (Brahmi) on cognitive function in healthy human subjects. Psychopharmacology (Berl). 2001;156(4):481–484. PubMed.
  7. Roodenrys S, Booth D, Bulzomi S, et al. Chronic effects of Brahmi (Bacopa monnieri) on human memory. Neuropsychopharmacology. 2002;27(2):279–281. PubMed.
  8. Stough C, Downey LA, Lloyd J, et al. Examining the nootropic effects of a special extract of Bacopa monniera on human cognitive functioning: 90 day double-blind placebo-controlled randomized trial. Phytother Res. 2008;22(12):1629–1634. PubMed.
  9. Calabrese C, Gregory WL, Leo M, et al. Effects of a standardized Bacopa monnieri extract on cognitive performance, anxiety, and depression in the elderly: a randomized, double-blind, placebo-controlled trial. J Altern Complement Med. 2008;14(6):707–713. PMC.
  10. Morgan A, Stevens J. Does Bacopa monnieri improve memory performance in older persons? Results of a randomized, placebo-controlled, double-blind trial. J Altern Complement Med. 2010;16(7):753–759. PubMed.
  11. Sathyanarayanan V, Thomas T, Einöther SJ, et al. Brahmi for the better? New findings challenging cognition and anti-anxiety effects of Brahmi (Bacopa monniera) in healthy adults. Psychopharmacology (Berl). 2013;227(2):299–306. PubMed.
  12. Lopresti AL, Smith SJ. The Effects of a Bacopa monnieri Extract (Bacumen) on Cognition, Stress, and Fatigue in Healthy Adults: A Randomized, Double-Blind, Placebo-Controlled Trial. Clin Drug Investig. 2025;45(12):967–982. PubMed.
  13. Pase MP, Kean J, Sarris J, et al. The cognitive-enhancing effects of Bacopa monnieri: a systematic review of randomized, controlled human clinical trials. J Altern Complement Med. 2012;18(7):647–652. PubMed.
  14. Kongkeaw C, Dilokthornsakul P, Thanarangsarit P, et al. Meta-analysis of randomized controlled trials on cognitive effects of Bacopa monnieri extract. J Ethnopharmacol. 2014;151(1):528–535. PubMed.
  15. Tiemtad P, Ingkaninan K, Temkitthawon P, et al. Comparative effects of Bacopa monnieri and Ginkgo biloba on cognitive functions: A systematic review and network meta-analysis. Phytomedicine. 2026;153:157915. PubMed.
  16. Basheer A, Agarwal A, Mishra B, et al. Use of Bacopa monnieri in the Treatment of Dementia Due to Alzheimer Disease: Systematic Review of Randomized Controlled Trials. Interact J Med Res. 2022;11(2):e38542. PubMed.
  17. Prabhakar S, Vishnu VY, Modi M, et al. Efficacy of Bacopa Monnieri (Brahmi) and Donepezil in Alzheimer’s Disease and Mild Cognitive Impairment: A Randomized Double-Blind Parallel Phase 2b Study. Ann Indian Acad Neurol. 2020;23(6):767–773. PubMed.
  18. Kean JD, Downey LA, Stough C. A systematic review of the Ayurvedic medicinal herb Bacopa monnieri in child and adolescent populations. Complement Ther Med. 2016;29:56–62. PubMed.
  19. Kean JD, Downey LA, Sarris J, et al. Effects of Bacopa monnieri (CDRI 08) in a population of males exhibiting inattention and hyperactivity aged 6 to 14 years: A randomized, double-blind, placebo-controlled trial. Phytother Res. 2022;36(2):996–1012. PubMed.
  20. Pravina K, Ravindra KR, Goudar KS, et al. Safety evaluation of BacoMind in healthy volunteers: a phase I study. Phytomedicine. 2007;14(5):301–308. PubMed.
  21. Ramasamy S, Kiew LV, Chung LY. Inhibition of human cytochrome P450 enzymes by Bacopa monnieri standardized extract and constituents. Molecules. 2014;19(2):2588–2601. PubMed.
  22. Acquarulo B, Tandon P, Macica CM. Suspected cholinergic toxicity due to cevimeline hydrochloride and Bacopa monnieri interaction: a case report. J Med Case Rep. 2022;16(1):253. PubMed.
  23. Kar A, Panda S, Bharti S. Relative efficacy of three medicinal plant extracts in the alteration of thyroid hormone concentrations in male mice. J Ethnopharmacol. 2002;81(2):281–285. PubMed.
  24. Singh A, Singh SK. Evaluation of antifertility potential of Brahmi in male mouse. Contraception. 2009;79(1):71–79. PubMed.
  25. Gościniak A, Stasiłowicz-Krzemień A, Szeląg M, et al. Bacopa monnieri: Preclinical and Clinical Evidence of Neuroactive Effects, Safety of Use and the Search for Improved Bioavailability. Nutrients. 2025;17(11):1939. PubMed.
  26. Mishra A, Mishra AK, Tiwari OP, et al. Studies on metals and pesticide content in some Ayurvedic formulations containing Bacopa monnieri L. J Integr Med. 2016;14(1):44–50. PubMed.
  27. World Anti-Doping Agency. The 2026 Prohibited List. In effect from January 1, 2026. WADA 2026 Prohibited List.