Ginkgo Biloba

Last Updated: July 22, 2023

Ginkgo biloba is the most commonly ingested herb for brain health. While it may boost cognition in older populations, this effect is not very reliable or generalizable.

Ginkgo Biloba is most often used for

What is Ginkgo biloba?

Ginkgo biloba (ginkgo) is a tree whose leaves are often used as a dietary supplement for the purposes of cognitive improvement. These leaves contain a variety of potentially bioactive compounds, including several types of flavonoids and terpenoids.

What are Ginkgo biloba’s main benefits?

Ginkgo biloba seems to improve aspects of cognitive function in people with dementia.[1] There is also preliminary evidence that ginkgo can improve cognitive function in healthy middle-aged people[2] and healthy older people.[3] It is unclear whether ginkgo can improve cognitive function in healthy younger people, as most studies on this population have reported no clear benefit.[4]

What are Ginkgo biloba’s main drawbacks?

No significant safety concerns associated with Ginkgo biloba leaf extract have been clearly identified in human clinical trials. Although case studies have indicated that ginkgo might increase bleeding risk,[5] a meta-analysis of 18 randomized controlled trials found no higher risk of bleeding in participants who took standardized extracts.[6] There have been rare reports of seizures among people with epilepsy who supplemented with ginkgo, perhaps due to stimulation of the enzymatic breakdown of anticonvulsant medication.[5] Finally, experiments in rodents have suggested that ginkgo extract may be carcinogenic.[7]

How does Ginkgo biloba work?

There is no well-established mechanism to explain how Gingko biloba improves cognitive function, but a few possibilities have been proposed. Among these are improved blood flow to the brain,[8] reduced oxidative stress,[9] and inhibition of the neurotoxic effects of amyloid beta.[9]

What else is Ginkgo Biloba known as?
Note that Ginkgo Biloba is also known as:
  • Tanakan
  • Tebonin
  • Rökan
  • Maidenhair
  • gingko
Ginkgo Biloba should not be confused with:
Dosage information

For cognitive enhancement, take 120-240mg, one to four hours before performance. To alleviate cognitive decline in older adults, take 40-120mg, three times a day. The supplement form of Ginkgo biloba is also called EGb-761 extract. It should be a 50:1 concentrated extract. Ginkgo biloba should be taken with meals.

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References
  1. ^Hashiguchi M, Ohta Y, Shimizu M, Maruyama J, Mochizuki MMeta-analysis of the efficacy and safety of Ginkgo biloba extract for the treatment of dementia.J Pharm Health Care Sci.(2015)
  2. ^Kaschel RSpecific memory effects of Ginkgo biloba extract EGb 761 in middle-aged healthy volunteersPhytomedicine.(2011 Nov 15)
  3. ^Mix JA, Crews WD JrA double-blind, placebo-controlled, randomized trial of Ginkgo biloba extract EGb 761 in a sample of cognitively intact older adults: neuropsychological findingsHum Psychopharmacol.(2002 Aug)
  4. ^Canter PH, Ernst EGinkgo biloba is not a smart drug: an updated systematic review of randomised clinical trials testing the nootropic effects of G. biloba extracts in healthy people.Hum Psychopharmacol.(2007-Jul)
  5. ^Mei N, Guo X, Ren Z, Kobayashi D, Wada K, Guo LReview of Ginkgo biloba-induced toxicity, from experimental studies to human case reports.J Environ Sci Health C Environ Carcinog Ecotoxicol Rev.(2017-Jan-02)
  6. ^Kellermann AJ, Kloft CIs there a risk of bleeding associated with standardized Ginkgo biloba extract therapy? A systematic review and meta-analysis.Pharmacotherapy.(2011-May)
  7. ^Rider CV, Nyska A, Cora MC, Kissling GE, Smith C, Travlos GS, Hejtmancik MR, Fomby LM, Colleton CA, Ryan MJ, Kooistra L, Morrison JP, Chan PCToxicity and carcinogenicity studies of Ginkgo biloba extract in rat and mouse: liver, thyroid, and nose are targets.Toxicol Pathol.(2014-Jul)
  8. ^Ameneh Mashayekh, Dzung L Pham, David M Yousem, Mercedes Dizon, Peter B Barker, Doris D M LinEffects of Ginkgo biloba on cerebral blood flow assessed by quantitative MR perfusion imaging: a pilot studyNeuroradiology.(2011 Mar)
  9. ^Singh SK, Srivastav S, Castellani RJ, Plascencia-Villa G, Perry GNeuroprotective and Antioxidant Effect of Ginkgo biloba Extract Against AD and Other Neurological Disorders.Neurotherapeutics.(2019-Jul)
Examine Database References
  1. Blood Flow - Gardner CD, Taylor-Piliae RE, Kiazand A, Nicholus J, Rigby AJ, Farquhar JWEffect of Ginkgo biloba (EGb 761) on treadmill walking time among adults with peripheral artery disease: a randomized clinical trialJ Cardiopulm Rehabil Prev.(2008 Jul-Aug)
  2. Intermittent Claudication Symptoms - Mouren X, Caillard P, Schwartz FStudy of the antiischemic action of EGb 761 in the treatment of peripheral arterial occlusive disease by TcPo2 determinationAngiology.(1994 Jun)
  3. Intermittent Claudication Symptoms - Bauer U6-Month double-blind randomised clinical trial of Ginkgo biloba extract versus placebo in two parallel groups in patients suffering from peripheral arterial insufficiencyArzneimittelforschung.(1984)
  4. Atherosclerotic Signs - Rodríguez M, Ringstad L, Schäfer P, Just S, Hofer HW, Malmsten M, Siegel GReduction of atherosclerotic nanoplaque formation and size by Ginkgo biloba (EGb 761) in cardiovascular high-risk patientsAtherosclerosis.(2007 Jun)
  5. Peripheral Vascular Disease Risk - Kuller LH, Ives DG, Fitzpatrick AL, Carlson MC, Mercado C, Lopez OL, Burke GL, Furberg CD, DeKosky ST; Ginkgo Evaluation of Memory Study InvestigatorsDoes Ginkgo biloba reduce the risk of cardiovascular eventsCirc Cardiovasc Qual Outcomes.(2010 Jan)
  6. Microcirculation - Suter A, Niemer W, Klopp RA new ginkgo fresh plant extract increases microcirculation and radical scavenging activity in elderly patientsAdv Ther.(2011 Dec)
  7. ADHD Symptoms - Salehi B, Imani R, Mohammadi MR, Fallah J, Mohammadi M, Ghanizadeh A, Tasviechi AA, Vossoughi A, Rezazadeh SA, Akhondzadeh SGinkgo biloba for attention-deficit/hyperactivity disorder in children and adolescents: a double blind, randomized controlled trialProg Neuropsychopharmacol Biol Psychiatry.(2010 Feb 1)
  8. Sleep Quality - Hemmeter U, Annen B, Bischof R, Brüderlin U, Hatzinger M, Rose U, Holsboer-Trachsler EPolysomnographic effects of adjuvant ginkgo biloba therapy in patients with major depression medicated with trimipraminePharmacopsychiatry.(2001 Mar)
  9. Libido - A J Cohen, B BartlikGinkgo biloba for antidepressant-induced sexual dysfunctionJ Sex Marital Ther.(Apr-Jun 1998)
  10. Schizophrenia symptoms - Doruk A, Uzun O, Ozşahin AA placebo-controlled study of extract of ginkgo biloba added to clozapine in patients with treatment-resistant schizophreniaInt Clin Psychopharmacol.(2008 Jul)
  11. Schizophrenia symptoms - Atmaca M, Tezcan E, Kuloglu M, Ustundag B, Kirtas OThe effect of extract of ginkgo biloba addition to olanzapine on therapeutic effect and antioxidant enzyme levels in patients with schizophreniaPsychiatry Clin Neurosci.(2005 Dec)
  12. Schizophrenia symptoms - Zhang XY, Zhou DF, Zhang PY, Wu GY, Su JM, Cao LYA double-blind, placebo-controlled trial of extract of Ginkgo biloba added to haloperidol in treatment-resistant patients with schizophreniaJ Clin Psychiatry.(2001 Nov)
  13. Tardive Dyskinesia Symptoms - Zhang XY, Zhang WF, Zhou DF, Chen da C, Xiu MH, Wu HR, Haile CN, Kosten TA, Kosten TRBrain-derived neurotrophic factor levels and its Val66Met gene polymorphism predict tardive dyskinesia treatment response to Ginkgo bilobaBiol Psychiatry.(2012 Oct 15)
  14. Attention - Attia A, Rapp SR, Case LD, D'Agostino R, Lesser G, Naughton M, McMullen K, Rosdhal R, Shaw EGPhase II study of Ginkgo biloba in irradiated brain tumor patients: effect on cognitive function, quality of life, and moodJ Neurooncol.(2012 Sep)
  15. Libido - Wheatley DTriple-blind, placebo-controlled trial of Ginkgo biloba in sexual dysfunction due to antidepressant drugsHum Psychopharmacol.(2004 Dec)
  16. Libido - Meston CM, Rellini AH, Telch MJShort- and long-term effects of Ginkgo biloba extract on sexual dysfunction in womenArch Sex Behav.(2008 Aug)
  17. Reaction Time - Kennedy DO, Scholey AB, Wesnes KAModulation of cognition and mood following administration of single doses of Ginkgo biloba, ginseng, and a ginkgo/ginseng combination to healthy young adultsPhysiol Behav.(2002 Apr 15)
  18. Processing Speed - Mix JA, Crews WD JrAn examination of the efficacy of Ginkgo biloba extract EGb761 on the neuropsychologic functioning of cognitively intact older adultsJ Altern Complement Med.(2000 Jun)
  19. Memory - Kennedy DO, Haskell CF, Mauri PL, Scholey ABAcute cognitive effects of standardised Ginkgo biloba extract complexed with phosphatidylserineHum Psychopharmacol.(2007 Jun)
  20. Memory - Mix JA, Crews WD JrA double-blind, placebo-controlled, randomized trial of Ginkgo biloba extract EGb 761 in a sample of cognitively intact older adults: neuropsychological findingsHum Psychopharmacol.(2002 Aug)
  21. Cognition - Santos RF, Galduróz JC, Barbieri A, Castiglioni ML, Ytaya LY, Bueno OFCognitive performance, SPECT, and blood viscosity in elderly non-demented people using Ginkgo bilobaPharmacopsychiatry.(2003 Jul)
  22. Cognition - Yancheva S, Ihl R, Nikolova G, Panayotov P, Schlaefke S, Hoerr R, GINDON Study GroupGinkgo biloba extract EGb 761(R), donepezil or both combined in the treatment of Alzheimer's disease with neuropsychiatric features: a randomised, double-blind, exploratory trialAging Ment Health.(2009 Mar)
  23. Cognition - Andrew B Scholey, David O KennedyAcute, dose-dependent cognitive effects of Ginkgo biloba, Panax ginseng and their combination in healthy young volunteers: differential interactions with cognitive demandHum Psychopharmacol.(2002 Jan)
  24. Cognitive Decline - Ihl R, Tribanek M, Bachinskaya N, GOTADAY Study GroupEfficacy and tolerability of a once daily formulation of Ginkgo biloba extract EGb 761® in Alzheimer's disease and vascular dementia: results from a randomised controlled trialPharmacopsychiatry.(2012 Mar)
  25. Cerebral Blood Flow - Ameneh Mashayekh, Dzung L Pham, David M Yousem, Mercedes Dizon, Peter B Barker, Doris D M LinEffects of Ginkgo biloba on cerebral blood flow assessed by quantitative MR perfusion imaging: a pilot studyNeuroradiology.(2011 Mar)
  26. Cognitive Decline - Napryeyenko O, Borzenko I; GINDEM-NP Study GroupGinkgo biloba special extract in dementia with neuropsychiatric features. A randomised, placebo-controlled, double-blind clinical trialArzneimittelforschung.(2007)
  27. Cognitive Decline - Kanowski S, Herrmann WM, Stephan K, Wierich W, Hörr RProof of efficacy of the ginkgo biloba special extract EGb 761 in outpatients suffering from mild to moderate primary degenerative dementia of the Alzheimer type or multi-infarct dementiaPharmacopsychiatry.(1996 Mar)
  28. Cognitive Decline - Herrschaft H, Nacu A, Likhachev S, Sholomov I, Hoerr R, Schlaefke SGinkgo biloba extract EGb 761® in dementia with neuropsychiatric features: a randomised, placebo-controlled trial to confirm the efficacy and safety of a daily dose of 240 mgJ Psychiatr Res.(2012 Jun)
  29. Cognitive Decline - Zhang SJ, Xue ZYEffect of Western medicine therapy assisted by Ginkgo biloba tablet on vascular cognitive impairment of none dementiaAsian Pac J Trop Med.(2012 Aug)
  30. Cognitive Decline - Le Bars PL, Katz MM, Berman N, Itil TM, Freedman AM, Schatzberg AFA placebo-controlled, double-blind, randomized trial of an extract of Ginkgo biloba for dementia. North American EGb Study Group.JAMA.(1997)
  31. Alzheimer's Disease Risk - DeKosky ST, Williamson JD, Fitzpatrick AL, Kronmal RA, Ives DG, Saxton JA, Lopez OL, Burke G, Carlson MC, Fried LP, Kuller LH, Robbins JA, Tracy RP, Woolard NF, Dunn L, Snitz BE, Nahin RL, Furberg CD; Ginkgo Evaluation of Memory (GEM) Study InvestigatorsGinkgo biloba for prevention of dementia: a randomized controlled trialJAMA.(2008 Nov 19)
  32. Acute Mountain Sickness Symptoms - Gertsch JH, Seto TB, Mor J, Onopa JGinkgo biloba for the prevention of severe acute mountain sickness (AMS) starting one day before rapid ascentHigh Alt Med Biol.(2002 Spring)
  33. Acute Mountain Sickness Symptoms - Gertsch JH, Basnyat B, Johnson EW, Onopa J, Holck PSRandomised, double blind, placebo controlled comparison of ginkgo biloba and acetazolamide for prevention of acute mountain sickness among Himalayan trekkers: the prevention of high altitude illness trial (PHAIT)BMJ.(2004 Apr 3)
  34. Acute Mountain Sickness Symptoms - Leadbetter G, Keyes LE, Maakestad KM, Olson S, Tissot van Patot MC, Hackett PHGinkgo biloba does--and does not--prevent acute mountain sicknessWilderness Environ Med.(2009 Spring)
  35. Acute Mountain Sickness Symptoms - Moraga FA, Flores A, Serra J, Esnaola C, Barriento CGinkgo biloba decreases acute mountain sickness in people ascending to high altitude at Ollagüe (3696 m) in northern ChileWilderness Environ Med.(2007 Winter)
  36. Acute Mountain Sickness Symptoms - Chow T, Browne V, Heileson HL, Wallace D, Anholm J, Green SMGinkgo biloba and acetazolamide prophylaxis for acute mountain sickness: a randomized, placebo-controlled trialArch Intern Med.(2005 Feb 14)
  37. Acute Mountain Sickness Symptoms - Roncin JP, Schwartz F, D'Arbigny PEGb 761 in control of acute mountain sickness and vascular reactivity to cold exposureAviat Space Environ Med.(1996 May)
  38. Tinnitus Symptoms - Seon-Sook Han, Eui-Cheol Nam, Jun Yeon Won, Kang Uk Lee, Wanjoo Chun, Hyun Kyung Choi, Robert Aaron LevineClonazepam quiets tinnitus: a randomised crossover study with Ginkgo bilobaJ Neurol Neurosurg Psychiatry.(2012 Aug)
  39. Tinnitus Symptoms - Hilton MP, Zimmermann EF, Hunt WTGinkgo biloba for tinnitusCochrane Database Syst Rev.(2013 Mar 28)
  40. Tinnitus Symptoms - Drew S, Davies EEffectiveness of Ginkgo biloba in treating tinnitus: double blind, placebo controlled trialBMJ.(2001 Jan 13)
  41. Nitric Oxide - Li XS, Zheng WY, Lou SX, Lu XW, Ye SHEffect of Ginkgo leaf extract on vascular endothelial function in patients with early stage diabetic nephropathyChin J Integr Med.(2009 Feb)
  42. Sleep Quality - Murray BJ, Cowen PJ, Sharpley ALThe effect of Li 1370, extract of Ginkgo biloba, on REM sleep in humansPharmacopsychiatry.(2001 Jul)
  43. Stroke Recovery - Zeng X, Liu M, Yang Y, Li Y, Asplund KGinkgo biloba for acute ischaemic strokeCochrane Database Syst Rev.(2005 Oct 19)
  44. Cognitive Decline - Vellas B, Coley N, Ousset PJ, Berrut G, Dartigues JF, Dubois B, Grandjean H, Pasquier F, Piette F, Robert P, Touchon J, Garnier P, Mathiex-Fortunet H, Andrieu S, GuidAge Study GroupLong-term use of standardised Ginkgo biloba extract for the prevention of Alzheimer's disease (GuidAge): a randomised placebo-controlled trialLancet Neurol.(2012 Oct)
  45. PMS Symptoms - Tamborini A, Taurelle RValue of standardized Ginkgo biloba extract (EGb 761) in the management of congestive symptoms of premenstrual syndromeRev Fr Gynecol Obstet.(1993 Jul-Sep)
  46. Intraocular Pressure - Wimpissinger B, Berisha F, Garhoefer G, Polak K, Schmetterer LInfluence of Ginkgo biloba on ocular blood flowActa Ophthalmol Scand.(2007 Jun)
  47. Intraocular Pressure - Quaranta L, Bettelli S, Uva MG, Semeraro F, Turano R, Gandolfo EEffect of Ginkgo biloba extract on preexisting visual field damage in normal tension glaucomaOphthalmology.(2003 Feb)
  48. Intraocular Pressure - Chung HS, Harris A, Kristinsson JK, Ciulla TA, Kagemann C, Ritch RGinkgo biloba extract increases ocular blood flow velocityJ Ocul Pharmacol Ther.(1999 Jun)
  49. PMS Symptoms - Ozgoli G, Selselei EA, Mojab F, Majd HAA randomized, placebo-controlled trial of Ginkgo biloba L. in treatment of premenstrual syndromeJ Altern Complement Med.(2009 Aug)
  50. Subjective Well-Being - Kaschel RSpecific memory effects of Ginkgo biloba extract EGb 761 in middle-aged healthy volunteersPhytomedicine.(2011 Nov 15)
  51. Blood Pressure - Mehlsen J, Drabaek H, Wiinberg N, Winther KEffects of a Ginkgo biloba extract on forearm haemodynamics in healthy volunteersClin Physiol Funct Imaging.(2002 Nov)
  52. Blood Pressure - Brinkley TE, Lovato JF, Arnold AM, Furberg CD, Kuller LH, Burke GL, Nahin RL, Lopez OL, Yasar S, Williamson JD; Ginkgo Evaluation of Memory (GEM) Study InvestigatorsEffect of Ginkgo biloba on blood pressure and incidence of hypertension in elderly men and womenAm J Hypertens.(2010 May)
  53. Blood Pressure - Gillian Keheyan, Lauren A Dunn, Wendy Louise HallAcute effects of Ginkgo biloba extract on vascular function and blood pressurePlant Foods Hum Nutr.(2011 Sep)
  54. Reaction Time - K. Wesnes, D. Simmons, M. Rook, P. SimpsonA double-blind placebo-controlled trial of tanakan in the treatment of idiopathic cognitive impairment in the elderlyHuman Psychopharmacology: Clinical and Experimental.()
  55. Cognitive Decline - Brautigam MR, Blommaert FA, Verleye G, Castermans J, Jansen Steur EN, Kleijnen JTreatment of age-related memory complaints with Ginkgo biloba extract: a randomized double blind placebo-controlled studyPhytomedicine.(1998 Dec)
  56. Cognitive Decline - Snitz BE, O'Meara ES, Carlson MC, Arnold AM, Ives DG, Rapp SR, Saxton J, Lopez OL, Dunn LO, Sink KM, DeKosky ST, Ginkgo Evaluation of Memory (GEM) Study InvestigatorsGinkgo biloba for preventing cognitive decline in older adults: a randomized trialJAMA.(2009 Dec 23)
  57. Memory - Bäurle P, Suter A, Wormstall HSafety and effectiveness of a traditional ginkgo fresh plant extract - results from a clinical trialForsch Komplementmed.(2009 Jun)
  58. Overall Cancer Risk - Biggs ML, Sorkin BC, Nahin RL, Kuller LH, Fitzpatrick ALGinkgo biloba and risk of cancer: secondary analysis of the Ginkgo Evaluation of Memory (GEM) StudyPharmacoepidemiol Drug Saf.(2010 Jul)
  59. Intermittent Claudication Symptoms - Thomson GJ, Vohra RK, Carr MH, Walker MGA clinical trial of Gingkco Biloba Extract in patients with intermittent claudicationInt Angiol.(1990 Apr-Jun)
  60. Intermittent Claudication Symptoms - Peters H, Kieser M, Hölscher UDemonstration of the efficacy of ginkgo biloba special extract EGb 761 on intermittent claudication--a placebo-controlled, double-blind multicenter trialVasa.(1998 May)
  61. Multiple Sclerosis Symptoms - Lovera JF, Kim E, Heriza E, Fitzpatrick M, Hunziker J, Turner AP, Adams J, Stover T, Sangeorzan A, Sloan A, Howieson D, Wild K, Haselkorn J, Bourdette DGinkgo biloba does not improve cognitive function in MS: a randomized placebo-controlled trialNeurology.(2012 Sep 18)
  62. Wrinkles - P Chuarienthong, N Lourith, P LeelapornpisidClinical efficacy comparison of anti-wrinkle cosmetics containing herbal flavonoidsInt J Cosmet Sci.(2010 Apr)
  63. Blood Flow - Boelsma E, Lamers RJ, Hendriks HF, van Nesselrooij JH, Roza LEvidence of the regulatory effect of Ginkgo biloba extract on skin blood flow and study of its effects on urinary metabolites in healthy humansPlanta Med.(2004 Nov)
  64. Cortisol - Jezova D, Duncko R, Lassanova M, Kriska M, Moncek FReduction of rise in blood pressure and cortisol release during stress by Ginkgo biloba extract (EGb 761) in healthy volunteersJ Physiol Pharmacol.(2002 Sep)
  65. Libido - Kang BJ, Lee SJ, Kim MD, Cho MJA placebo-controlled, double-blind trial of Ginkgo biloba for antidepressant-induced sexual dysfunctionHum Psychopharmacol.(2002 Aug)
  66. Raynaud's Phenomenon Symptoms - Bredie SJ, Jong MCNo significant effect of ginkgo biloba special extract EGb 761 in the treatment of primary Raynaud phenomenon: a randomized controlled trialJ Cardiovasc Pharmacol.(2012 Mar)
  67. Raynaud's Phenomenon Symptoms - Choi WS, Choi CJ, Kim KS, Lee JH, Song CH, Chung JH, Ock SM, Lee JB, Kim CMTo compare the efficacy and safety of nifedipine sustained release with Ginkgo biloba extract to treat patients with primary Raynaud's phenomenon in South Korea; Korean Raynaud study (KOARA study)Clin Rheumatol.(2009 May)
  68. Vitiligo Symptoms - Parsad D, Pandhi R, Juneja AEffectiveness of oral Ginkgo biloba in treating limited, slowly spreading vitiligoClin Exp Dermatol.(2003 May)
  69. Vitiligo Symptoms - Orest Szczurko, Neil Shear, Anna Taddio, Heather BoonGinkgo biloba for the treatment of vitilgo vulgaris: an open label pilot clinical trialBMC Complement Altern Med.(2011 Mar 15)
  70. Autism Symptoms - Niederhofer HFirst preliminary results of an observation of Ginkgo Biloba treating patients with autistic disorderPhytother Res.(2009 Nov)
  71. Autism Symptoms - Hasanzadeh E, Mohammadi MR, Ghanizadeh A, Rezazadeh SA, Tabrizi M, Rezaei F, Akhondzadeh SA double-blind placebo controlled trial of Ginkgo biloba added to risperidone in patients with autistic disordersChild Psychiatry Hum Dev.(2012 Oct)
  72. Anxiety Symptoms - Woelk H, Arnoldt KH, Kieser M, Hoerr RGinkgo biloba special extract EGb 761 in generalized anxiety disorder and adjustment disorder with anxious mood: a randomized, double-blind, placebo-controlled trialJ Psychiatr Res.(2007 Sep)
  73. Ocular Blood Flow - Park JW, Kwon HJ, Chung WS, Kim CY, Seong GJShort-term effects of Ginkgo biloba extract on peripapillary retinal blood flow in normal tension glaucomaKorean J Ophthalmol.(2011 Oct)