Common names: Ginkgo, Maidenhair tree, Tanakan, R?kan, Tebonin, Ginkgobil, Kaveri, Ginkgobl?tter, Arbe aux quarante écus (forty coin tree).

Botanical name: Ginkgo biloba 

Nutritional Support at a Glance: Used as nutritional support by persons with Dementia, Depression, Peripheral Artery Disease (PAD), Intermittent Claudication, Postphlebitis Syndrome, Raynaud’s Disease, Multiple Sclerosis, Cerebral Vascular Insufficiency, Retinopathy, Diabetic Retinopathy, Macular Degeneration, Neuralgia, Neuropathy, Inner Ear Dysfunction, Vertigo, Tinnitus, Premenstrual Syndrome (PMS), Impotence (ED), Vascular Fragility, Heart Disease, Stroke, Memory Loss, Headaches, Allergies, Asthma. 

Notice to Consumers:
No information is provided as an enticement to purchase and in accordance with section 201(g) of the Food, Drug and Cosmetic Act, is not intended to treat, prevent, cure or mitigate any disease and is for your perusal and to be used in concert with your physician.

To view product formulations: Arbe aux quarante écus (forty coin tree) (Ginkgo biloba)

Origin: The Arbe aux quarante écus (forty coin tree) (Ginkgo biloba), from the family Ginkgoacea, dates back 200 million years and is the only known survivor of the Permian or Triassic period. It is native to China and was transported many years ago to Japan, but was once found in North America and Europe until the Ice Age. The Chinese revered the tree, planting it around the Emperors Palace and Shen Nung the Emperor/sage in the Pen Tsao Ching (The Classic of Herbs) penned it “good for the heart and lungs.” Due to its leaves turning a brilliant gold color in the autumn it was called, “the forty coin tree.” In Chinese medicine it was used to treat asthma and cold hands, feet, and referred to its ability to “benefit the brain” also the Chinese and Japanese ate the roasted seeds as a digestive aid and to prevent drunkenness. The seeds were also used as a food source as early as the Han dynasty (206 BC to 220 AD.) and compared to walnuts and as a substitute for lotus seeds. In 1436, Ginkgo is identified as a treatment for head sores and freckles. Japanese texts mention Ginkgo’s use at tea ceremonies and as a desert as early as 1492. Recorded consumption of the red dyed seeds at weddings is found as early as 1578. In the 18th century they became a side dish for sake and today the grilled nuts are still eaten with sake in Japan. 

Arbe aux quarante écus (forty coin tree) (Ginkgo biloba) was associated by the Ayurvedic’s to longevity and used an elixir as such. The tree was introduced to Europe in 1730 and although planted in parks and around streets, they had no knowledge of its medicinal value and therefore little is mentioned in European herbal/medical texts. The German physician and botanist, Engelbert Kaempfer was the first European to catalog the tree and the flavonoid kaempferol bears his name. Carl Linnaeus named the tree Ginkgo biloba in 1771. William Hamilton brought the Ginkgo tree to the U. S. in 1784 and it became popular as an ornamental tree because of its resistance to disease, insects, and pollutants. A group of German scientists in the 1960’s investigated the effects of the herb on circulation and found the leaves quite active and soon the concentrated flavonoid extract was patented. Ginkgo’s standardized extract is today one of Europe’s most prescribed medicinal herbal compounds by herbalists and traditional medical doctors.

Parts Used Medicinally: The leaf and it’s extract are used medicinally, however, the inner seeds are also sold in the Orient as bai gou usually for roasting, but the seed coat and embryo are considered inedible due to its foul smell and bitterness.

Traditional and/or Historical Use: The Arbe aux quarante écus (forty coin tree) (Ginkgo biloba) nuts were almost exclusively used in traditional Chinese medicine for treating asthma and polyuria, however, the use of its leaf has been known for thousands of years for treatment to benefit the brain, for coughs and asthma, as well as helping the body eliminate filaria, a parasitic nematode that causes severe inflammatory obstruction and elephantiasis, but since the extensive research on Ginkgo over the past 40 years the Chinese have adopted the leaf and extract (GBE) into their materia medica as well.

There is no well documented traditional use, but recent pharmacological studies support consideration for disorders caused by peripheral blood flow, i.e. atherosclerosis, diabetic vascular disease, Raynaud’s syndrome and its anti-PAF activity supports use for asthma, ischemia, thrombosis, immunological reactions, shock, allergic reactions and as an anti-oxidant for reperfusion injury and ischemia protection with evidence that it may be useful for preventing migraine headaches. Clinical trials are use-supportive of symptoms and disorders caused by cerebral blood flow restrictions, i.e. impairment of memory and cognition, tinnitus, anxiety, depression, dizziness, stroke, headaches, peripheral artery disease, intermittent claudication, acute cochlear deafness, early stages of Alzheimers, multifarct dementia, congestive dysmenorrheal, macular degeneration in the elderly and hypoxia. Arbe aux quarante écus (forty coin tree) (Ginkgo biloba) is in the United States Pharmacopeia-National Formulary (USP 23-NF 18.

The standardized GBE is covered by a positive Commission E monograph for symptomatic treatment of dementia syndromes, primary degenerative dementia, vascular dementia, including memory deficit, concentration disorders, depression, dizziness, tinnitus, headache, increasing pain-free walking distances in peripheral arterial occlusive disease of intermittent claudication and with vertigo and tinnitus of vascular and involuntary origin.

Active Biochemical’s or Phytochemical’s and/or Mechanisms of Action: The active phytochemical’s are (0.5%-1.0%)mono-, di-, and triglycosides of the flavones, quercetin, kaempferol, isorhamnetin, and the flavonoid esters coumeric acid; terpenoids (terpene lactones, bilobalide, ginkgolides A, B, C, J; bioflavonoids, ginkgolic acids, sterols, procyanidins, and poly saccharides and the research has been performed on a complex array of components standardized to 24% ginkgo flavone glycosides and 6% terpenoids, ginkgolides and bilobalide, which are unique to Ginkgo and are not found in any other plant species with the total extract composite having a synergistic activity offering greater effectiveness that any single constituent. 

Arbe aux quarante écus (forty coin tree) (Ginkgo biloba) exerts a vascular effect on the lining of blood vessels by stimulating (EDRF) and prostacyclin and protects brain cell and nerve membrane unsaturated fatty acids from free radical damage and normalizes circulation of the hippocampus and striatum by increased perfusion activity. GBE and ginkgolide B acts at the hypothalamic level reducing corticotrophin-releasing hormone expression and secretion. Peripheral artery disease (PAD) is medically treated with pentoxifylline (Trental), but numerous studies demonstrate GBE and even exercise alone is equal to or more effective than pentoxifylline; increased pain-free walking times and distances were noted as well as increased blood flow determined by Doppler and plethysmographic measurements. The decreased blood lactate levels noted are indicative of increased circulatory elimination of exercise waste by-products thus effectively promoting endurance with decreased pain from pH shift which demonstrates superiority over pentoxifylline and many standard medical protocols.

The use of Arbe aux quarante écus (forty coin tree) (Ginkgo biloba) over a 2 year period increased pain-free walking distance by 300%. Extrapolation of these results imply efficacy in the use of GBE in diabetic peripheral vascular disease, postphlebitis syndrome, acrocyanosis, and Raynaud’s disease. Ginkgo is also very useful in the treatment of erectile dysfunction in patients due to a lack of blood flow and when compared to papaverine injection, GBE demonstrated superior efficacy probably due to GBE’s ability to dramatically increase blood flow without increasing blood pressure and the results of GBE are more remarkable with long-term use. GBE demonstrated ability to block platelet-activating factor (PAF) by counteracting the PAF skin injection reddened area (flare) by 62.4% mean and hive volume (wheal) by 60% mean. Since PAF is a primary chemical mediator of inflammation, allergies and asthma, GBE may also be useful for these conditions as well. GBE’s antidepressant effect was noted in a double-blind study of 40 patients aged 51-78 years with confirmed depression that poorly benefited from antidepressant drugs and by one month on GBE, the Hamilton Depression Scale score dropped from 14 to 7 and by 2 months the HDS score had dropped to 4.5 in the GBE group compared to a drop from 14 to only 13 in the control group. GBE also improved long-visual acuity in diabetic retinopthy and macular degeneration with a protective action noted experimentally.

The major symptoms of short-term memory loss, depression, tinnitus, headache, vertigo were impressively regressed in well designed studies using GBE. Improvement in performance of memory testing was significant in the elderly as well as reaction time in young women due to GBE’s ability to improve the rate of nerve cell neural and cholinergic transmission. PMS symptoms of breast tenderness, fluid retention and increased capillary permeability were reduced in a PMS suffering population of 165 women aged 18-45 years was effective as determined by the physician and patient as well as improvements in psychological assessments noted.

Recommended Dosage: When purchasing herbal products make sure that the standardization is not from a certificate of analysis (COA) prior to manufacturing, but from a post-manufacturing analysis, otherwise the ingredients may vary in potency by as much as 10 fold. Commercial and profession strength and grade varies from manufacturer to manufacturer…buyer beware! Arbe aux quarante écus (forty coin tree) (Ginkgo biloba) should be standardized to provide a minimum of 24% ginkgo flavone glycosides and 6% terpenes usually in a 150 mg base of non-standardized Ginkgo biloba. While most research is done with a standardized dose of GBE given at 40 mg 3 times daily, some studies are performed using 80 mg 3 times daily. The conclusion of most studies is that Arbe aux quarante écus (forty coin tree) (Ginkgo biloba) should be taken at least 12 weeks to obtain maximum benefit. Professional capsules are commonly available in 40 mg and 80 mg with recommended dosing of 120 mg to 240 mg per day of Arbe aux quarante écus (forty coin tree) (Ginkgo biloba extract) (GBE). Tinctures are available, but it may not be possible to obtain sufficient amounts for efficacious results using a 1:5 ratio of crude extract.

Toxicity, Cautions, Contra-Indications: Arbe aux quarante écus (forty coin tree) (Ginkgo biloba) is considered to be very safe when used as a GBE encapsulated product, but crude preparations of the fruit pulp have produced severe allergic reactions and ingestion of small amounts of fruit or pulp have also caused severe gastrointestinal inflammatory and allergic reactions. LD50 studies confirm that high dosing does not show renal or hepatic impairment and no teratogenic effects or mutagenic activity was observed.

CAUTION: The consumption of Arbe aux quarante écus (forty coin tree) (Ginkgo biloba) seeds and stems or very large amounts of leaves as food has demonstrated toxicity because of the high content of the toxin 4’-O-methylpyroxidine, which can cause vitamin B6 deficiency and convulsions, however, it should be noted that the presence of bilobalide decreased convulsion severity. The practice of consuming the roasted seeds by Japanese is not considered dangerous, but should be limited for children. Clinical trials confirm the safety of Ginkgo extract with only 2 adverse events reported out of 314,000 patient-years of use. One reported case of spontaneous iris bleeding occurred in a 70 year-old male who was also taking 325 mg of aspirin/day for 3 years following coronary bypass surgery. There are no known contra-indications for the use of GBE, but decreased clotting ability should be considered when taking GBE with warfarin or aspirin. There are no reported cases of overdose associated with GBE.

Drug Interactions: George T. Grossberg, M.D. & Barry Fox, Ph.D reports, ”Taking ginkgo biloba with these drugs may increase the risk of bleeding or bruising: abciximab, acemetacin, alteplase, antithrombinIII, argatroban, aspirin, aspirin and dipyridamole, bivalirudin, celecoxib, choline magnesium trisalicylate, choline salicylate, clopidogrel, dalteparin, danaparoid, diclofenac, diflunisal, dipyridamole, dipyrone, drotrecogin, enoxaparin, eptifibatide, etodolac, etoricoxib, fenoprofen, flurbiprofen, fondaparinux, heparin, hydrocodone and aspirin, hydrocodone and ibuprofen, ibritumomab, ibuprofen, indobufen, indomethacin, ketoprofen, ketorolac, lepirudin, magnesium salicylate, meclofenamate, mefenamic acid, meloxicam, nabumetone, nadroparin, naproxen, niflumic acid, nimesulide, oxaprozin, piroxicam, reteplase, rofecoxib, salsalate, streptokinase, sulindac, tenecteplase, tenoxicam, tiaprofenic acid, ticlopidine, tinzaparin, tirofiban, tolmetin, urokinase, valdecoxib, warfarin. Taking ginkgo with these drugs may reduce the effectiveness of the drug and worsen hypertension: chlorothiazide, hydrochlorothiazide, hydrochlorothiazide and trimterene, hydroflumethiazide, olmesartan and hydrochlorothiazide, polythiazide, trichloromethiazide, xipamide. Taking ginkgo biloba with these drugs may increase the risk of seizures: acetazolamide, amitriptyline, amobarbital, amoxapine, barbexaclone, bupropion, carbamazepine, ciprofloxacin, clonazepam, clorazepate, desipramine, diazepam, doxepin, ethosuximide, felbamate, fosphenytoin, gabapentin, ganciclovir, imipramine, lamotrigine, levetiracetam, lorazepam, mephobarbital, methlphenidate, metoclopramide, methylphenidate, metonidazole, moxifloxacin, nortriptyline, ofloxacin, olanzepin, oxazepam, oxcarbazepine, pentobarbital, Phenobarbital, phenytoin, primidone, prochlorperazine, quetiapine, thiopental, tiagabine, topiramate, tramadol, valproic acid, venlafaxine, vigabatrin, zonisamide. Taking ginkgo biloba with these drugs may disrupt blood sugar control: acarbose, glipizide, glyburide, insulin, metformin, miglitol, pioglitazone, repaglinide, rosiglitazone. Taking ginkgo biloba with these drugs may increase the effects of the drug: iproniazid, moclobemide, phenelzine, selegiline, tranylcypromine. Taking ginkgo biloba with these drugs may be harmful: fluoxetine-may cause or increase serotonin syndrome, agitation, rapid heart rate, flushing, heavy sweating, and possibly even death, nifedipine-may increase blood levels of the drug, papaverine-may increase the risk of adverse effects.”

General References: Balch, J. and Balch, P., (1997) Prescription for Nutritional Healing. Garden City Park, New York: Avery Publishing Group. Castleman, M., (1991) The Healing Herbs. Emmaus, Pennsylvania: Rodale Press. Chopra, D., (1993) Alternative Medicine. Fife, Washington: Future Medicine Publishing, Inc. Flynn, R. and Roest, M., (1995) Your Guide to Standardized Herbal Products. Prescott, Arizona: One World Press. Murray, M., (1996) Encyclopedia of Nutritional Supplements. Unites States of America: Prima Publishing. Murray, M. and Pizzorno, J., (1998) Encyclopedia of Natural Medicine. United States of America: Prima Publishing. Null, G., (1998) The Complete Encyclopedia of Natural Healing. New York, New York: Kensington Publishing Corp. Werbach, M., (1993) Nutritional Influences of Illness. Tarzana, California: Third Line Press. Melvin R. Werbach, M.D. & Jeffrey Moss, D.D.S., C.N.S., C.C.N. (1999) Textbook of Nutritional Medicine. Third Line Press, Inc. Tarzana, CA. Simon Mills, MCPP, FNIMH, MA & Kerry Bone MCPP FNHAA FNIMH BSc (Hons) (2000) Principles and Practices of Phytotherapy. New York, NY Churchill Livingstone. Joseph Pizzorno, Jr. & Michael Murray, (1999) Textbook of Natural Medicine. New York, NY, Churchill Livingstone. M. Murray, N.D.(1995) The Healing Power of Herbs. New York, NY, Gramercy Books. Melvin R. Werbach M.D. & Michael T Murray, N.D., (2000) Botanical Influences on Illness. A Sourcebook of Clinical Research. Tarzana, CA, Third Line Press. George T. Grossberg, M.D. & Barry Fox, Ph.D. (2007) The Essential Herb-Drug-Vitamin Interaction Guide. New York, NY, Broadway Books. James F. Balch, M.D. & Mark Stengler, N.D., (2004) Prescription for Natural Cures. Hoboken, NJ, John Wiley & Sons, Inc.

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