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Ginkgo and bleeding.

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Hmmm. So does ginkgo cause bleeding or not?

I was looking for data on one herb or the other, and stumbled on ABC's HerbClips. They're cool, if rather too biased for my tastes.

Anyway, this clip caught my eye: "Systematic Review Casts Doubt on Correlation of Ginkgo Use with Bleeding". (also referenced here). (Ernst E, Canter PH, Coon JT. Does Ginkgo biloba increase the risk of bleeding? A systematic review of case reports. Perfusion. 2005;18:52-56. - I'd have linked to the abstract, but it looks like it's not online yet.) In this bit of paper research, E. Ernst (the new Tyler. Bleh.) & Co. look into papers which reported bleeding with gingko, and say that the likelihood of gingko having caused bleeding was "likely" (8/10) in only one of the 12 cases found. In 11 cases it was "possible" (5-7/10). None of the cases were "unevaluable".

Funny, though, to only have that three-tiered scale of "unevaluable" (0-3), "possible" (4-7), and "likely" (8-10) - I'd have added two more: "unlikely" and "certain".

They were smart enough to exclude single constituents. Bravo for this all too rare display of common sense in herbal scientific research!


I'd like to know more altogether about ginko vis a vis bleeding, or blood thinning. The reason is personal; after taking 4 drops of tincture daily for 1 week, my menses returned (after a three-month hiatus). I'm 51 and perfectly willing to do without that anymore. Of course, nothing is so simple as to allow one to say, "It was the ginko", but I do wonder.

Anyway, I think my information on ginko is outdated, and if anyone is willing to point me to a good source (or to comment) I'd be grateful.



I also saw the reference in HerbalGram, and included it in the Wikipedia page on Ginkgo before reading it. When I tried to find it, I realized that either the reference wasn't to the Ingenta journal called "perfusion" (as their Vol. 18 was 2003, and pp. 52-56 of 2005 or 2003 were different articles), or else the reference was badly wrong. If anyone has a clue, please feel free to fix the Wikipedia reference.

Google scholar finds no such article.
There's no such article in Perfusion.

I found something similar on medline:
"Bent S, Goldberg H, Padula A, Avins AL.: Spontaneous bleeding associated with ginkgo biloba: a case report and systematic review of the literature.. J Gen Intern Med. 2005 Jul;20(7):657-61."

From the abstract of that paper: "RESULTS: Fifteen published case reports described a temporal association between using ginkgo and a bleeding event. Most cases involved serious medical conditions, including 8 episodes of intracranial bleeding. However, 13 of the case reports identified other risk factors for bleeding. Only 6 reports clearly described that ginkgo was stopped and that bleeding did not recur. Bleeding times, measured in 3 reports, were elevated when patients were taking ginkgo."

Would somebody with access to the full article please post what the "other risk factors" for 13 of the 15 examined cases were? Thanks!