Ginkgo (Ginkgo biloba) Research

Latin Name: Ginkgo biloba 

Family: Ginkgoaceae

The ginkgo herb is most researched for its memory enhancing strengths.  It may also help with altitude sickness and glaucoma, but more research is necessary.  Now if I could only remember how to spell ginkgo!

The listings of research below represent a compilation of scientific articles found on the species, with a very brief overview description of each article/study. Research found is catalogued by therapeutic action. This categorized compilation of research articles does not necessarily imply that there are adequate results to demonstrate safe and/or effective human use.

GENERAL

• A review of human clinical trials and other studies on echinacea, garlic, ginger, ginkgo, St John’s wort, and valerian are summarized.  From:  Barrett, B., Kiefer, D., & Rabago, D. (1999). Assessing the risks and benefits of herbal medicine: an overview of scientific evidence. Alternative Therapies in Health and Medicine, 5(4), 40.
• Ginkgo has been used for centuries by the Chinese, documented as a remedy for respiratory complaints and diarrhea back to the 1400’s.  Europeans used it in the 1700’s to improve circulation.  Modern studies have shown it useful in improving flow to the brain, helping with memory, and dementia.  It may also help with tinnitus and leg cramps.  From:  Weil, A., et al. (2010).  National Geographic Guide to Medicinal Herbs.  National Geographic.  Washington D.C.
• WebMD. (n.d.).  Ginkgo.  Retrieved in March, 2019.  Retrieved from www.webmd.com.

SAFETY

• Taken in small, standardized doses, ginkgo is generally safe. Avoid large and non-standardized usage, which can cause digestive upset, nervousness, and excessive bleeding (WebMD).
• Uncooked seeds can be very poisonous.  Excessive intake of cooked seeds and crude leaves can also be hazardous.
• Touching the fresh seeds can cause contact dermatitis similar to poison ivy.  From:  Weil, A., et al. (2010).  National Geographic Guide to Medicinal Herbs.  National Geographic.  Washington D.C.
• Avoid with pregnancy and lactation (WebMD).
• Children should not take the seeds (WebMD).
• May interfere with certain medications such as anticoagulants, anxiety medications, anti-depressants, seizure medications, and more (WebMD).

MEMORY

• A double blind, placebo controlled, 14 week, parallel group, repeated assessment, multi-centre trial study of 256 healthy middle aged volunteers who took an extract of Ginkgo biloba and Panax ginseng demonstrated improved memory.  From: Wesnes, K. A., Ward, T., McGinty, A., & Petrini, O. (2000). The memory enhancing effects of a Ginkgo biloba/Panax ginseng combination in healthy middle-aged volunteers. Psychopharmacology, 152(4), 353-361.
• A total of 188 middle aged volunteers took Ginkgo biloba extract for six weeks and demonstated improved memory recall.  From: Kaschel, R. (2011). Specific memory effects of Ginkgo biloba extract EGb 761 in middle-aged healthy volunteers. Phytomedicine, 18(14), 1202-1207.
• In this double blind placebo controlled parallel group study of 31 patients over 50 years old and with a mild to moderate memory impairment, taking a gingko biloba extract over 6 months showed beneficial results in their cognitive function.  From:  Rai, G. S., Shovlin, C., & Wesnes, K. A. (1991). A double-blind, placebo controlled study of Ginkgo biloba extract (‘tanakan’) in elderly outpatients with mild to moderate memory impairment. Current medical research and opinion, 12(6), 350-355.
• Ginkgo biloba showed to be promoising for those with Alzheimer’s in this systematic review.  More research is necessary. From: Janßen, I. M., Sturtz, S., Skipka, G., Zentner, A., Garrido, M. V., & Busse, R. (2010). Ginkgo biloba in Alzheimer’s disease: a systematic review Ginkgo biloba bei Alzheimer Demenz: eine systematische Übersicht. Wiener Medizinische Wochenschrift, 160(21-22), 539-546.
• A placebo-controlled, double blind study with 20 young health adults showed ginkgo and ginseng to improve cognitive performance.  From:  Kennedy, D. O., Scholey, A. B., & Wesnes, K. A. (2001). Differential, dose dependent changes in cognitive performance following acute administration of a Ginkgo biloba/Panax ginseng combination to healthy young volunteers. Nutritional neuroscience, 4(5), 399-412.
• In a 52 week study of 202 patients with dementia, a ginkgo supplement was safe and effective in improving cognition and social function. From:  Le Bars, P. L., Katz, M. M., Berman, N., Itil, T. M., Freedman, A. M., & Schatzberg, A. F. (1997). A placebo-controlled, double-blind, randomized trial of an extract of Ginkgo biloba for dementia. Jama, 278(16), 1327-1332.

ANTIDEPRESSIVE / ANXIETY

• Multiple studies on the uses of herbs for mood disorders were reviewed.  Promising herbs included:  Hypericum perforatum (St. John’s wort), Piper methysticum (kava), Echium amoenum, Crocus sativus, Rhodiola rosea (golden root), Matricaria recutita (Roman chamomile), Ginkgo biloba (ginkgo), Passiflora incanata (passionflower), and Scutellaria lateriflora (blue skullcap).  From:  Sarris, Jerome, et al. “Herbal medicine for depression, anxiety and insomnia: a review of psychopharmacology and clinical evidence.” European neuropsychopharmacology 21.12 (2011): 841-860.
• In a study of 170 patients with anxiety, taking a ginkgo supplement was well tolerated and better than the placebo in reducing symptoms.  From:  Woelk, H., Arnoldt, K. H., Kieser, M., & Hoerr, R. (2007). Ginkgo biloba special extract EGb 761® in generalized anxiety disorder and adjustment disorder with anxious mood: a randomized, double-blind, placebo-controlled trial. Journal of psychiatric research, 41(6), 472-480.
• In a review of research, ten herbs offered human trails and demonstrated potential in reducing anxiety by affecting the Gamma-aminobutyric acid (GABA) inhibitory neurotransmitter. These included: kava, valerian, pennywort, hops, chamomile, ginkgo biloba, passionflower, ashwagandha, skullcap, and lemon balm. From: Savage, K., Firth, J., Stough, C., & Sarris, J. (2018). GABA‐modulating phytomedicines for anxiety: A systematic review of preclinical and clinical evidence. Phytotherapy research, 32(1), 3-18.

SCHIZOPHRENIA

• In a thorough review of scientific research, the author concluded high quality evidence to support kava, passionflower, and galphimia for anxiety and St. John’s wort and saffron for depression. The author found promising evidence for turmeric for depression, ashwagandha for anxiety and depression, and for ginkgo as an adjunct treatment to schizophrenia. From: Sarris, J. (2018). Herbal medicines in the treatment of psychiatric disorders: 10‐year updated review. Phytotherapy research, 32(7), 1147-1162.

TINNITUS

• In a double blind randomized 12 week study of 197 patients with tinnitus, a ginkgo supplement was safer and just as effective as pentoxifylline in reducing tinnitus symptoms.  From:  Procházková, K., Šejna, I., Skutil, J., & Hahn, A. (2018). Ginkgo biloba extract EGb 761® versus pentoxifylline in chronic tinnitus: a randomized, double-blind clinical trial. International journal of clinical pharmacy, 40(5), 1335-1341.

VISION

• In this human study, Ginkgo biloba extract significantly increased end diastolic velocity in the opthalmic artery and could be useful to treat glaucomatous optic neuropathy and other ischemic ocular diseases.  From:  Chung, H. S., Harris, A., Kristinsson, J. K., Ciulla, T. A., Kagemann, C., & Ritch, R. (1999). Ginkgo biloba extract increases ocular blood flow velocity. Journal of ocular pharmacology and therapeutics, 15(3), 233-240.
• Ginkgo biloba extract reduced preexisting visual field damage in some patients with normal tension glaucoma.  From:  Quaranta, L., Bettelli, S., Uva, M. G., Semeraro, F., Turano, R., & Gandolfo, E. (2003). Effect of Ginkgo biloba extract on preexisting visual field damage in normal tension glaucoma. Ophthalmology, 110(2), 359-362.  Link:  http://dx.doi.org/10.1016/S0161-6420(02)01745-1
• In this small population sample of people with senile macular degeneration, those treated with ginkgo had a statistically significant improvement in long distance visual acuity.  From:  Lebuisson, D. A., Leroy, L., & Rigal, G. (1986). Treatment of senile macular degeneration with Ginkgo biloba extract. A preliminary double-blind drug vs. placebo study. Presse medicale (Paris, France: 1983), 15(31), 1556-1558.

​​ALTITUDE SICKNESS

• Ginkgo reduced mountain sickness in participants normally  living at sea level.  From:  Moraga, F. A., Flores, A., Serra, J., Esnaola, C., & Barriento, C. (2007). Ginkgo biloba decreases acute mountain sickness in people ascending to high altitude at Ollagüe (3696 m) in northern Chile. Wilderness & environmental medicine, 18(4), 251-257.
• In a double blind study, one day of pretreatment with ginkgo 60 mg significantly reduced the severity of altitude sickness from a  rapid ascent from sea level to 4205 meters. From:   Gertsch, J. H., Seto, T. B., Mor, J., & Onopa, J. (2002). Ginkgo biloba for the prevention of severe acute mountain sickness (AMS) starting one day before rapid ascent. High altitude medicine & biology, 3(1), 29-37.

​​ANTIOXIDANT

• Fluid extracts of maidenhair tree (Ginkgo biloba), motherwort (Leonurus cardiaca) and hawthorn (Crataegus monogyna) showed antioxidant activity against  free radicals.  From:  Bernatoniene, J., Kucinskaite, A., Masteikova, R., Kalveniene, Z., Kasparaviciene, G., & Savickas, A. (2008). The comparison of anti-oxidative kinetics in vitro of the fluid extract from maidenhair tree, motherwort and hawthorn. Acta poloniae pharmaceutica, 66(4), 415-421.

ANTI-INFLAMMATORY

• Turmeric, myrrh, and ginkgo extracts were just as effective as aspirin in having an anti-inflammatory action in vitro.  From:  Motar, A. A., Hussein, R. A., & Abdulbary, M. (2017). Anti-inflammatory effect of turmeric plant (Curcuma longa L.) rhizomes and myrrh (Commiphora myrrha L.) gums and ginkgo Ginkgo biloba L. leaves (tablets) extracts. karbala journal of pharmaceutical sciences, (13), 59-69.

MENOPAUSE

• In a study of 180 postmenopausal women ages 45-55, taking 40 mg of a Ginkgo biloba tablet and 2-3 drops of aroma of geranium, rose, fennel, and lavender 3 times a day for 6 weeks reduced sexual disfunction compared to the placebo, gingko only, and aromatherapy only groups.  From:  Malakouti, J., Jabbari, F., Jafarabadi, M. A., Javadzadeh, Y., & Khalili, A. F. (2017). The impact of ginkgo biloba tablet and aromatherapy inhaler combination on sexual function in females during postmenopausal period: A double-blind randomized controlled trial. Int J Womens Health Reprod Sci, 5, 129-136.

HYPOLIPIDEMIC

• A compilation of research showed the following herbs to have a hypolipidemic effect:  yarrow, onion, garlic, dill, celery, burdock, oats, barberry, cabbage, chili pepper, safflower, chicory, chickpea, bitter orange, orange, guggul, coriander, cranberry, melon, pumpkin, artichoke, ginseng, eugenol, schelelecht, ginkgo, soy, walnut, apple, nutmeg, red yeast rice, miswak, evening primrose, basil, bulacy, orchis, avocado, plantain, blond plotitago, green bean, purslane, black cherry, pomegranate, milk thistle, brinjal, tomato, tamarind, thea, thyme, fenugreek, bilberry, grape, ginger, and corn.  From:  Rouhi-Boroujeni, H., Rouhi-Boroujeni, H., Khoddami, M., Khazraei, H. R., Dehkordil, E. B., & Rafieian-Kopaei, M. (2017). Hypolipidemic herbals with diuretic effects: A systematic review. In Biol. Sci (Vol. 8, pp. 21-28).

ANALGESIC

• In a review of research, plants used to treat neuropathic pain include: Vernonia cinerea, Ocimum sanctum, Ferula hermonis, Sambucus nigra, Salvia officinalis, Moringa oleifera, Harpagophytum procumbens, Momordica charantia, Butea monosperma, Punica granatum, Commiphora mukul, Ginkgo biloba, Crocus sativus , Cymbopogon martinii, Sinomenium acutum, Euterpe oleracea, Matricaria chamomilla, Nigella sativa, Aconiti tuber, Emblica officinalis, Phyllanthus amarus, Artemisia dracunculus, Allium sepa, and Allium sativum. From: Verma, S., Jain, C. P., Chauhan, L. S., & Shukla, A. K. (2016). A review on treatment and management of neuropathic pain with herbal folk drugs. Asian Journal of Pharmacy and Pharmacology, 2(5), 104-110.

NEUROPROTECTIVE

• This article provided a review of research on the medicines and herbs used to treat neurological disorders. From: Sivaraman, D., Anbu, N., Kabilan, N., Kumar, M. P., Shanmugapriya, P., & Christian, G. J. (2019). REVIEW ON CURRENT TREATMENT STRATEGY IN ALZHEIMER’S DISEASE AND ROLE OF HERBS IN TREATING NEUROLOGICAL DISORDERS. Int J Trans Res Ind Med, 1(1), 33-43.

Compiled by: Kathy Sadowski

Updated: 9/12/19