A daily dose of the herbal remedy gingko biloba may help prevent brain damage after stroke, new research suggests.
The findings, published online in the medical journal Stroke, have been shown only in mice, but researchers say the studies support theories that ginkgo biloba may be a useful treatment for stroke patients.
A mouse study suggests ginkgo biloba may be a promising treatment for stroke patients. (Ruth Fremson/The New York Times)“It’s still a large leap from rodent brains to human brains, but these results strongly suggest that further research into the protective effects of ginkgo is warranted,” said lead researcher Sylvain Doré, an associate professor in the Johns Hopkins department of anesthesiology and critical care medicine, in a press release. “If further work confirms what we’ve seen, we could theoretically recommend a daily regimen of ginkgo to people at high risk of stroke as a preventive measure against brain damage.”
In the series of mouse studies, scientists induced stroke in animals, including some that had previously been given various doses of ginkgo biloba. Normal mice that had been pretreated with the herb had 51 percent less neurological dysfunction than untreated mice, and areas of brain damage were reduced by 48 percent in the ginkgo group.
“Our results suggest that some element or elements in ginkgo actually protect brain cells during stroke,” Dr. Doré said.
About 700,000 people experience a stroke in the United States annually. Nearly nine out of 10 stroke sufferers experience ischemic stroke, which is caused by a blocked artery in the brain. The stroke itself can cause brain damage by depriving brain cells of blood. But toxic oxygen molecules, known as free radicals, also can cause additional damage after the clot is cleared.
Ginkgo biloba, which comes from a Chinese tree with fan-shaped leaves, may work to prevent further brain damage because it increases levels of an enzyme that eliminates free radicals around the stroke site in the brain.
“Ginkgo has long been touted for its positive effects on the brain and is even prescribed in Europe and Asia for memory loss,” Dr. Doré said. “Now we have a possible understanding for how ginkgo actually works to protect neurons from damage.”
Patients should talk to their doctor before taking gingko. One concern is that gingko thins blood, and patients at risk for strokes and seizures are warned against taking it. Ginkgo biloba should be discontinued at least 36 hours before surgery due to the risk of increased bleeding. Patients with bleeding or clotting disorders, or those who use warfarin, insulin and several other drugs, should also not take ginkgo.
To learn more about the risks and benefits of ginkgo, including warnings about its use, go to About Herbs, a Web site created by the Memorial Sloan-Kettering Cancer Center.
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18 Comments
Ginkgo is a wonderful herbal supplement. After two years of continuous use, I am able to recall vast amounts of information from my long and short term memory, which was extremely beneficial when I took and passed the 2007 bar exam.I first realized that it actually works when all of sudden I able to recite the lyrics to song I have not heard in donkey years.
— Michael S. ESQAh, the old research joke. It’s a great time to be a mouse! Cures for cancers, cures for diabetes, and now a significant treatment for ischemic strokes. Now only if the NIH or the herbal supplement industry would fund the clinical trials in humans.
— JasonUntil last year, we enjoyed many years of free Ginkgo nuts from trees along with street in Kingston, NY. Plenty of harvest gave us year long of supply for CHAWAN MUSHI (Japanese style of steamed egg, soup stock with Ginkgo nuts.).
Somehow these wonderful Ginkgo trees were cut perhaps due to the odor fruits generate. I wish this article will help understanding preserving this wonderful plant from our city streets.
— Masashi.MWhat did experts in this field, who have nothing to do with this study, have to say about the results? It’s one thing to just report what the researcher involved says, but I think medical journalism should go beyond that, particularly when we’re in the world of so-called alternative medicines (sCAMs).
The link to the “About Herbs” website seems fine, until you start reading some of their articles. Their front page claim is that they are evidence-based. However, their acupuncture page discusses the medically meaningless “Qi Energy” as the believed mechanism for the effects of acupuncture, without acknowledging that such ‘Qi Energy’ is untestable pseudoscience.
Tara, have you read this blog?:
http://www.sciencebasedmedicine.com
It’s a wonderful resource, written by doctors and medical experts, about the fuzzy region where medicine and pseudoscience intersect.
— PaulInteresting study. I’ll read more about it, since a member of my family suffered an aneurism a couple of years ago - I wonder if the study mentions anything about non-ischemic strokes?
— Doug BroussardJust a warning: When I was taking anti-depressants (serzone, then Effexor), I absolutely could NOT take ginko! It made me incredibly cranky and irritable, which I never was with or without the meds, then or now. And I was simply drinking a name-brand tea with ginko and peppermint.
I’m not on the anti-depressants anymore, so maybe I’ll give ginko a try again.
— Janet VAs long as we do not know precisely which substances in the Ginkgo extract affect the ischemic brain tissue and what underlying molecular mechanisms reduce the impact of the stroke, medication with Ginkgo extracts is ill-advised. Read more at: http://brainmindinst.blogspot.com/
— Peter MelzerI guess it’s time for a scientific double-blind (treatment, control) study to validate the hypothesis.
Since, I know of no serious side effects from the use of Ginkgo, physicians might use it on high risk cardiovascular
patients now.
Then, after a well designed study with a large enough sample is done and replicated, it can be recommended for
— David Chowes, New York Citya larger population.
I can’t go that far, #7. Plenty of medications, ancient and new, are used that we don’t fully understand. Yes, of course we want to understand them. But this is how science works–by fits, starts, experiments here and there, yes anecdotally often, more controlled elsewhere. Everything in medicine starts with an accident or an anecdote or a funny idea.
And in meantime people are sick, and willful and persistent that they won’t be held off for twenty years until every molecular mechanism is elucidated. Yes, they’ll waste money sometimes on things that don’t help—but plenty of FDA-approved options do not help the illnesses they are supposed to help!
Further, this is just another item originally drawn from the vast and wonderful Chinese pharmacopeia—just as many medicines in use today are synthetics of Western plant products.
And stroke patients have SO few treatments now—both my parents stroked, and the biological treatments offered were really perfunctory.
— appleSomething does not compute here. The article says that ginko should not be taken by those at risk for stroke. Isn’t it supposed to prevent stroke??
TPP, maybe you left out the key word “hemorrhagic?”
— jackThese articles should be vetted by a doctor.
There’s a lot of potential misinformation here…
— CraigWould like to know more and have further research be done I think there may be possibilities for many medicinal purposeses.
— LarryErrr…from the article: “…these results strongly suggest that further research into the protective effects of ginkgo is warranted,” thus the idea of needing more information is already part of the text…. Rushing out to your neighborhood herbalist or oriental items shop is not a good idea. I have taken ginko for years after a doctor diagnosed possible “hardening” of blood vessels in my brain. The doctor didn’t prescribe it, but what was prescribed caused me to pass out and clunk my cranium on a piece of furniture! The dosage in Chinese said 1, 3 times a day… Wrong apparently should be 1 every 3 days! Causes excess acid in (my) tummy anyway. No more symptoms of said hardening, at 70+ I roller blade and ride my Honda CRM off the road. Gingko? dunno, but ‘ll keep taking it while the research goes on.
— Richard GrahamMs. Parker-Pope
This article is well written, but I think is worth a follow-up. If in fact “those who use warfarin, insulin and several other drugs, should also not take ginkgo,” holds, it’s highly likely that people taking aspirin should also be cautious. Aspirin doesn’t have as strong an effect as warfarin, of course, but I believe far more believe are taking it and it remains a powerful drug. I learned this researching a possible choice betwen the two, and was surprised to discover how potent aspirin is in this.
I’m a tech writer, not a physician, so could be off-base. Your article is sure to influence many people’s choices, so I urge you to check this further, and if appropriate follow up the in clear terms.
— Dave BursteinDave Burstein
to post # 8: “Since, I know of no serious side effects from the use of Ginkgo”….
According to the Natural Medicines Comprehensive Database (www.naturaldatabase.com) which maintains evidence-based safety monographs on herbal and natural medicines, there are a number of adverse effects associated with ginkgo biloba. The list is long and mainly deals with bleeding. It highlights that there is rarely such a thing as a free lunch….most drugs, even “natural” ones, have side effects, many of which can be serious and problematic, and that they need to be weighed along with any benefit one may derive from taking the drug. Here is a brief excerpt:
“Orally, ginkgo leaf extract is well tolerated in typical doses. It can cause mild gastrointestinal (GI) upset, headache, dizziness, palpitations, constipation, and allergic skin reactions. Large doses can cause restlessness, diarrhea, nausea, vomiting, lack of muscle tone, and weakness. Spontaneous bleeding is one of the most concerning potential side effects associated with ginkgo. There are several published case reports linking ginkgo to episodes of minor to severe bleeding; however, not all case reports clearly establish ginkgo as the cause of bleeding. In most cases, other bleeding risk factors were also present including taking other medications, old age, liver cirrhosis, recent surgery, and other conditions. In most cases, bleeding occurred after several weeks or months of taking ginkgo.”
This website, while you have to pay to subscribe, is a wonderful resource on natural medicines and provides extensive bibliographies so that you can go directly to the research paper and read the results for yourself.
— wlsI have been taking 40 mg of Ginko (the smallest dosage one can buy) once a day for years. It was prescribed by a cardiologist long ago. I found that it lessened greatly my tinnitus (ringing in the ears.) I also take wafarin, a blood thinner. The wafarin dosage is adjusted for the ginko. I have been taking this combination for over 10 years now. No problems, at least so far.
roy
— roy lechtreckTotal confusion is the result of reading this article, and its comments.
— Shalom FreedmanDoes this supplment in fact decrease the risk of stroke? Or does it increase it for those who have not yet had stroke, and provide some repair for those who have suffered stroke?
And what in fact are the drugs which this supplment should not be taken with?
We have manufactured gingko biloba for about 12 years and have not had single case of toxicity reported. I personally take it for tinnitus and it reduces both the severity and the number. I can’t say that it helps in memory as this is not a problem I have,but I have heard some encouraging reportls on peripheral artery disease.
bill connelly
— william connelly