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Drugs and Health Products

Monograph: Ginkgo Biloba

This monograph is intended to serve as a guide to industry for the preparation of Product Licence Applications (PLA) and labels for natural health product market authorization. It is not intended to be a comprehensive review of the medicinal ingredient. It is a referenced document to be used as a labelling standard. Notes: Text in parentheses is additional optional information which can be included on the PLA and product labels at the applicant's discretion. The solidus (/) indicates that the terms are synonyms or that the statements are synonymous. Either term or statement may be selected by the applicant.

Date: 2009-06-24

NHPID Name

Ginkgo biloba (USDA 2008)

Proper Name(s)

Ginkgo biloba L. (Ginkgoaceae) ( USDA 2008 )

Common Name(s)

Source Material

Leaf ( Birks et al. 2007 )

Route Of Administration

Oral

Dosage Form(s)

  • The acceptable pharmaceutical dosage forms include, but are not limited to capsules, chewables (e.g. gummies, tablets), liquids, powders, strips or tablets.
  • This monograph is not intended to include foods or food-like dosage forms such as bars, chewing gums or beverages.

Use(s) or Purpose(s)

Statement(s) to the effect of:

Dose(s)

Adults:

Preparation: All Standardised Extracts

Dose(s): 4 - 12 Grams per day, dried leaves

See Appendix 1 for examples of appropriate dosage preparations and frequencies of use, according to cited references. The purpose of Appendix 1 is to provide guidance to industry.

Duration of use

Risk Information

Statement(s) to the effect of:

Caution(s) and Warning(s):
  • Consult a health care practitioner prior to use if you are pregnant or breastfeeding  (Blumenthal et al. 2000, WHO 1999)
  • Consult a health care practitioner prior to use if you are taking medications for diabetes, high blood pressure, or seizures  (Brinker 2010)

Contraindication(s):
Do not use if you are taking health products that affect blood coagulation (e.g. blood thinners, clotting factor replacements, acetylsalicylic acid, ibuprofen, fish oils, vitamin E) as this may increase the risk of spontaneous bleeding  (Brinker 2010, Bent et al. 2005)

Known Adverse Reaction(s):
No statement is required

Non-medicinal ingredients

Must be chosen from the current Natural Health Products Ingredients Database and must meet the limitations outlined in the database.

Specifications

  • The finished product specifications must be established in accordance with the requirements described in the NHPD Quality of Natural Health Products Guide.
  • The medicinal ingredient must comply with the requirements outlined in the Natural Health Products Ingredient Database (NHPID).
  • The medicinal ingredient may comply with the specifications outlined in the following pharmacopoeial monographs: 'Ginkgo Leaf' published in the British Pharmacopoeia, 'Ginkgo Leaf (Ginkgonis folium)' published in the European Pharmacopoeia, or 'Ginkgo', 'Powdered Ginkgo Extract', 'Ginkgo Capsules' and 'Ginkgo Tablets' published in the USP.

References cited

  • Bent S, Goldberg H, Padula A, Avins AL. Spontaneous bleeding associated with ginkgo biloba: a case report and systematic review of the literature. Journal of General Internal Medicine 2005;20(7):657-661.
  • Birks J, Grimley EV, Van Dongen M. Ginkgo biloba for cognitive impairment and dementia (Review). Oxfordshire (UK): The Cochrane Database of Systematic Reviews; 2007, Issue 2. Art. No.: CD003120. DOI: 10.1002/14651858.CD003120.pub2
  • Blumenthal M, Goldberg A, Brinckmann J, editors. Herbal Medicine: Expanded Commission E Monographs. Boston (MA): Integrative Medicine Communications; 2000.
  • Boelsma E, Lamers RJ, Hendriks HF, Van Nesselrooij JH, Roza L. Evidence of the regulatory effect of Ginkgo biloba extract on skin blood flow and study of its effects on urinary metabolites in healthy humans. Planta Medica 2004;70(11):1052-1057.
  • BP 2008: British Pharmacopoeia, Volume 1. Londron (UK): British Pharmacopoeia Commission. The Stationary Office.
  • Brinker F. Online Updates and Additions to Herb Contraindications and Drug Interactions, 3rd edition. Sandy (OR): Eclectic Medical Publications; 2010. [Accessed 2015 June 4]. Available from: http://www.eclecticherb.com/emp/updatesHCDI.html
  • Cieza A, Maier P, Pöppel E. Effects of Ginkgo biloba on mental functioning in healthy volunteers. Archives of Medical Research 2003;34(5):373-381.
  • Crews WD, Harrison DW, Griffin ML, Falwell KD, Crist T, Longest L, Hehemann L, Rey ST. The neuropsychological efficacy of Ginkgo preparations in healthy and cognitively intact adults: a comprehensive review. HerbalGram: The Journal of the American Botanical Council 2005;67:43-62.
  • Elsabagh S, Hartley DE, Ali O, Williamson EM, File SE. Differential cognitive effects of Ginkgo biloba after acute and chronic treatment in healthy young volunteers. Psychopharmacology 2005;179(2):437-446.
  • European Pharmacopoeia, 6th edition. Strasbourg (France): Directorate for the Quality of Medicines and HealthCare of the Council of Europe (EDQM).; 2008
  • Grässel E. [Effect of Ginkgo-biloba extract on mental performance. Double-blind study using computerized measurement conditions in patients with cerebral insufficiency]. Fortschritte der Medizin 1992;110(5):73-76 (in German).
  • Kennedy DO, Scholey AB, Wesnes KA. The dose-dependent cognitive effects of acute administration of Ginkgo biloba to healthy young volunteers. Psychopharmacology 2000;151(4):416-423.
  • Le Bars PL, Katz MM, Berman N, Itil TM, Freedman AM, Schatzberg AF. A placebo-controlled, double-blind, randomized trial of an extract of Ginkgo biloba for dementia. North American EGb Study Group. The Journal of the American Medical Association 1997;278(16):1327-1332.
  • McGuffin M, Kartesz JT, Leung AY, Tucker AO, editors. 2000. Herbs of Commerce, 2nd edition. Austin(TX): American Herbal Products Association.
  • Mehlsen J, Drabaek H, Wiinberg N, Winther K. Effects of a Ginkgo biloba extract on forearm haemodynamics in healthy volunteers. Clinical Physiology and Functional Imaging 2002;22(6):375-378.
  • Mix JA, Crews WD. A double-blind, placebo-controlled, randomized trial of Ginkgo biloba extract EGb 761 in a sample of cognitively intact older adults: neuropsychological findings. Human Psychopharmacology: Clinical and Experimental 2002;17(6):267-277.
  • Mix JA, Crews WD. An examination of the efficacy of Ginkgo biloba extract EGb761 on the neuropsychologic functioning of cognitively intact older adults. Journal of Alternative and Complementary Medicine 2000;6(3):219-229.
  • Moulton PL, Boyko LN, Fitzpatrick JL, Petros TV. The effect of Ginkgo biloba on memory in healthy male volunteers. Physiology and Behavior 2001;73(4):659-665.
  • Pittler MH, Ernst E. Ginkgo biloba extract for the treatment of intermittent claudication: a meta-analysis of randomized trials. The American Journal of Medicine 2000;108(4):276-281.
  • Santos RF, Galduróz JC, Barbieri A, Castiglioni ML, Ytaya LY, Bueno OF. Cognitive performance, SPECT, and blood viscosity in elderly non-demented people using Ginkgo biloba. Pharmacopsychiatry 2003;36(4):127-133.
  • Stough C, Clarke J, Lloyd J, Nathan PJ. Neuropsychological changes after 30-day Ginkgo biloba administration in healthy participants. The International Journal of Neuropsychopharmacology 2001;4(2):131-134.
  • USDA 2008: ARS, National Genetic Resources Program. Germplasm Resources Information Network (GRIN). National Germplasm Resources Laboratory, Beltsville (MD). [Accessed 2008-01-21]. Available at http://www.ars-grin.gov/cgi-bin/npgs/html/tax_search.pl
  • USP 32 : United States Pharmacopeial Convention. 2009. United States Pharmacopeia and the National Formulary (USP 32 - NF 27). Rockville (MD): The United States Pharmacopeial Convention.
  • WHO 1999: World Health Organization. WHO Monographs on Selected Medicinal Plants, Volume 1. Geneva (CH): World Health Organization; 1999.

References reviewed

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  • Beers MH, Berkow R, editors. The Merck Manual of Diagnosis and Therapy, 17th edition. Whitehouse Station (NJ): Merck & Co., Inc; 1999.
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  • Blumenthal M, Hall T, Goldberg A, Kunz T, Kinda K, editors. 2003. The ABC Clinical Guide to Herbs. Austin (TX): American Botanical Council
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  • Brautigam MRH, Blommaert FA, Verleye G, Castermans J, Jansen Steur ENH, Kleijnen J. Treatment of age-related memory complaints with Ginkgo biloba extract: a randomized double blind placebo-controlled study. Phytomedicine 1998;5(6):425-434.
  • Bush TM, Rayburn KS, Holloway SW, Sanchez-Yamamoto DS, Allen BL, Lam T, So BK, Tran de H, Greyber ER, Kantor S, Roth LW. Adverse interactions between herbal and dietary substances and prescription medications: a clinical survey. Alternative Therapies in Health and Medicine 2007;13(2):30-35.
  • Canter PH, and Ernst E. Ginkgo 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. Human Psychopharmacology 2007;22:265-278.
  • Carlson JJ, Farquhar JW, DiNucci E, Ausserer L, Zehnder J, Miller D, Berra K, Hagerty L, Haskell WL. Safety and efficacy of a ginkgo biloba-containing dietary supplement on cognitive function, quality of life, and platelet function in healthy, cognitively intact older adults. Journal of the American Dietetic Association 2007;107(3):422-432.
  • Dartigues JF, Carcaillon L, Helmer C, Lechevallier N, Lafuma A, Khoshnood B. Vasodilators and nootropics as predictors of dementia and mortality in the PAQUID cohort. Journal of the American Geriatrics Society 2007;55(3):395-399.
  • Destro MWB, Speranzini MB, Cavalheiro Filho C, Destro T, Destro C. Case report: bilateral haematoma after rhytidoplasty and blepharoplasty following chronic use of Ginkgo biloba. British Journal of Plastic Surgery 2005;58(1):100-101.
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  • Ellingwood F. 1983. American Materia Medica, Therapeutics and Pharmacognosy. Sandy (OR): Eclectic Medical Publications [Reprint of 1919 original].
  • Fessenden JM, Wittenborn W, Clark L. Ginkgo biloba: a case report of herbal medicine and bleeding postoperatively from a laparoscopic cholecystectomy. The American Surgeon 2001;67(1):33-35.
  • Fong KCS, Kinnear PE. Retrobulbar haemorrhage associated with chronic Gingko biloba ingestion. Postgraduate Medical Journal 2003;79(935):531-532.
  • Gerhardt G, Rogalla K, Jaeger J. [Drug therapy of disorders of cerebral performance. Randomized comparative study of dihydroergotoxine and Ginkgo biloba extract]. Fortschritte der Medizin 1990;108(19):384-388 (in German).
  • Gessner B, Voelp A, Klasser M. Study of the long-term action of a Ginkgo biloba extract on vigilance and mental performance as determined by means of quantitative pharmaco-EEG and psychometric measurements. Arzneimittel-Forschung 1985;35(9):1459-1465.
  • Gilbert GJ. Ginkgo biloba. Neurology 1997;48(4):1137.
  • Granger AS. Ginkgo biloba precipitating epileptic seizures. Age and Ageing 2001;30(6):523-525.
  • Greenblatt DJ, von Moltke LL, Luo Y, Perloff ES, Horan KA, Bruce A, Reynolds RC, Harmatz JS, Avula B, Khan IA, Goldman P. Ginkgo biloba does not alter clearance of flurbiprofen, a cytochrome P450-2C9 substrate. Journal of Clinical Pharmacology 2006;46(2):214-221.
  • Halama P, Bartsch G, Meng G. [Disorders of brain performance of vascular origin. Randomized double-blind study of the effectiveness of Gingko biloba extract]. Fortschritte der Medizin 1988;106(19):408-412 (in German).
  • Hofferberth B. [The effect of Ginkgo biloba extract on neurophysiological and psychometric measurement results in patients with psychotic organic brain syndrome. A double-blind study against placebo]. Arzneimittel-Forschung 1989;39(8):918-922 (in German).
  • Hofferberth B. The efficacy of EGb 761 in patients with senile dementia of the Alzheimer type: a double-blind, placebo-controlled study on different levels of investigation. Human Psychopharmacology: Clinical and Experimental 1994;9(3):215-222.
  • Huang SY, Jeng C, Kao SC, Yu JJ, Liu DZ. Improved haemorrheological properties by Ginkgo biloba extract (Egb 761) in type 2 diabetes mellitus complicated with retinopathy. Clinical Nutrition 2004;23(4):615-621.
  • Jellin JM. Natural Medicines Comprehensive Database: Ginkgo. Stockton (CA): Therapeutic Research Faculty; 1995-2007. [Accessed 2008-04-02]. Available from: http://www.naturaldatabase.com/(S(cruaemi5ulot20m4icegh545))/nd/Search.aspx?cs=&s=ND&pt=100&id=333&ds=adverse
  • Jiang X, Williams KM, Liauw WS, Ammit AJ, Roufogalis BD, Duke CC, Day RO, McLachlan AJ. Effect of ginkgo and ginger on the pharmacokinetics and pharmacodynamics of warfarin in healthy subjects. British Journal of Clinical Pharmacology 2005;59(4):425-32.
  • Kanowski S, HerrmannWM, Stephan K, Wierich W, Hörr R. Proof 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 dementia. Pharmacopsychiatry 1996;29(2):47-56.
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  • Kudolo GB, Wang W, Javors M, Blodgett J. The effect of the ingestion of Ginkgo biloba extract (EGb 761) on the pharmacokinetics of metformin in non-diabetic and type 2 diabetic subjects—a double blind, placebo-controlled, crossover study. Clinical Nutrition 2006;25(4):606-616.
  • Kudolo GB. The effect of 3-month ingestion of Ginkgo biloba extract (EGb 761) on pancreatic beta-cell function in response to glucose loading in individuals with non-insulin-dependent diabetes mellitus. Journal of Clinical Pharmacology 2001;41(6):600-611.
  • Le Bars PL, Velasco FM, Ferguson JM, Dessain EC, Kieser M, Hoerr R. Influence of the severity of cognitive impairment on the effect of the Ginkgo biloba extract EGb 761 in Alzheimer's disease. Neuropsychobiology 2002;45(1):19-26.
  • Mancini M, Agozzino B, Bompani R. [Clinical and therapeutic effects of Ginkgo biloba extract (GBE) compared to placebo in the treatment of patients affected by senile psychorganic dementia on an arteriosclerotic basic]. Gazzetta Medica Italiana Archivio per le Scienze Mediche 1993;152(3):69-80 (in Italian).
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Appendix 1: Examples of dosage preparations, frequencies of use and directions for use

Leaf:

Standardized extract:

  • Dried extract equivalent to 4 g dried leaf, per day (50:1, 80 mg) (Santos et al. 2003)
  • Dried extract equivalent to 3-4 g dried leaf, 2 to 3 times per day (50:1, 60-80 mg) (Elsbagh et al. 2005; Boelsma et al. 2004; Cieza et al. 2003; Mehlsen et al. 2002; Mix and Crews 2002; Moulton et al. 2001; Stough et al. 2001; Kennedy et al. 2000; Mix and Crews 2000; Pittler and Ernst 2000)