Ginkgo
biloba extract (GBE) is known to thin the blood
and increase blood flow. This is particularly helpful
in the small capillaries of the brain, eyes and
ears and is just one of a number of reasons why
ginkgo is helpful for tinnitus.
Over the years I have been frequently
asked if it is safe to take Arches Tinnitus Relief
Formula®, which contains GBE, along with other
blood thinning supplements and medications. In this
article we will explore the subject of ginkgo and
other blood thinners and the various supplements
and medications that can be safely used and those
that pose potential complications.
For our discussion here please
note that whenever I say ginkgo or Ginkgo biloba,
I am always referring to the standard 24/6 Ginkgo
biloba extract. Also note that there are many prescription
and nonprescription blood thinners on the market.
In this paper I refer to three common blood thinners:
Coumadin, Plavix and aspirin. All are popular, each
one is used for different reasons and while all
thin the blood, they do so in different ways.
PAF Blocker
First, it is necessary to understand the mechanisms
by which ginkgo thins blood and increases blood
flow. It does this in two different ways. Ginkgolide
B, one of the constituents of Ginkgo biloba, is
a potent inhibitor of excess platelet-activating
factor (PAF) by blocking the binding of PAF to its
receptor. (1)
PAF
is made in the blood from platelets and causes them
to aggregate or “clump” together. Under
normal conditions, this action is necessary for
the formation of blood clots to stop bleeding. With
excessive PAF, blood clots and atherosclerotic plaque
begin to build up. Atherosclerosis is the leading
cause of heart attack and stroke.
An excess of PAF in the bloodstream
also causes allergic reactions, which can lead to
bronchial constriction, where the bronchial tube
closes down. It can lead to life threatening inflammation
of the airways that induce asthma-like symptoms.
It causes a drop in blood pressure and reduced volume
of blood pumped by the heart, which can lead to
shock and possible death.
(2)
Ginkgo biloba has many cardio-protective
effects and the antagonism of PAF is one of them.
We’ve all seen those TV ads for Plavix where
the platelets are partially obstructing a blood
vessel. By taking Plavix, they begin to reduce and
dissolve. This is the primary function of Plavix;
reducing PAF. In this sense, Plavix and ginkgo are
similar. However, PAF reduction is only one of the
many positive functions of ginkgo.
Vasodilation
The second way ginkgo increases blood flow is through
vasodilation, especially in the micro-capillaries
that carry blood to the brain, eyes and ears.
Vasodilation is the process by
which the blood vessels relax and dilate, allowing
increased blood flow. This process allows more blood
to reach places where it is required to supply nutrients.
At the same time, ginkgo strengthens blood vessel
walls, reducing leakage and preventing hemorrhagic
stroke.
One
study showed that Ginkgo biloba was very helpful
for patients with coronary artery disease (CAD)
because it significantly improved blood flow through
vasodilation. Ginkgo significantly improved blood
flow through the descending coronary artery and
the brachial artery (in the upper arm) saw increased
blood flow of 69.75%. (3)
It is also helpful for intermittent claudicating,
a peripheral vascular disease, where poor circulation
causes pain while walking. (4)
Increased Bleeding with
Ginkgo?
In the 1990s there was some speculation that taking
Ginkgo biloba posed the problem of increased bleeding.
There were a few reports of people using ginkgo
and having a subdural hematoma, or bleeding on the
brain. These reports were very few and anecdotal
in nature. There was no clinical evidence that this
was the case.
Nonetheless, one doctor posted
a warning that received wide circulation on the
Internet. This report has been widely criticized
as there have been numerous clinical studies to
determine if ginkgo increased bleeding time or led
to hemorrhage. Bleeding time is the time it takes
to form a clot, which stops the bleeding.
A paper published by the Dr. Willmar
Schwabe Company of Germany (developer of GBE) cites
several clinical studies in this area. One study
on combing ginkgo with acetylsalicylic acid (aspirin)
proved that there are no indications of a greater
risk of hemorrhaging with ginkgo alone or in combination
with aspirin. (5)
Another study was conducted due
to reports of spontaneous bleeding. This study reported
“no major modification of bleeding time and
volume was observed for any of the subjects”
and “Platelet function was not modified by
treatment.” (6)
Yet another study investigated
Ginkgo biloba on hemostatic parameters (the slowing
or stopping of bleeding). The study’s main
outcome measures were bleeding time, coagulation
parameters and platelet activity. The study concluded
“Among the 29 coagulation and bleeding parameters
assessed, none showed any evidence of an inhibition
of blood coagulation and platelet aggregation through
EGb 761(GBE). Further the study did not reveal any
evidence to substantiate a causal relationship between
the administration of EGb 761 (GBE) and hemorrhagic
complications”. (7)
So Ginkgo does not cause bleeding
in healthy people. The issue is: what can we combine
it with that will not cause concerns and what should
we be careful about.
Coumadin is a powerful anticoagulant
that acts by inhibiting Vitamin K-dependent coagulation
factors. As noted above, Plavix is an inhibitor
of platelet activating factor. These drugs, and
others like them, thin the blood. They are hundreds
of times more potent than Ginkgo biloba but thin
the blood in much the same way.
Doctors prescribe these medications
to patients in order to thin the blood as much as
possible to reduce the possibility of heart attack
or stroke. Adding Ginkgo biloba to the mixture without
the doctor’s knowledge and understanding may
thin the blood too much and increase the risk of
bleeding, either internally or externally. This
is a very dangerous situation that can lead to bleeding
problems.
There are no adverse interactions
between ginkgo and these medications; they are simply
cumulative in nature. It is possible to take them
together but it must be done under the supervision
of the prescribing physician. The doctor will typically
lower the dosage of the anticoagulant medication
to accommodate the increased blood thinning ability
of ginkgo.
This normally requires a couple
of follow-up blood tests to make sure there is enough
coagulation to stop bleeding. Once everything is
in balance, the two products can be taken together
indefinitely. The prescribing physician must be
willing to balance the effects of anticoagulants
and ginkgo. Some doctors are opposed to the use
of herbal supplements and may not be cooperative.
OTC Bloodthinners
There are many supplements, foods and over-the-counter
medications that are blood thinning agents. Aspirin
is also an antagonist to PAF. Vitamin E, garlic
and fish oil all have blood thinning capabilities.
Aspirin is prescribed for many people with heart
conditions primarily because it is a PAF antagonist.
It is perfectly safe for most people
to combine any and all of these over-the-counter
products with ginkgo provided it is done in moderation.
Those who have a tendency to bleed easily will want
to be cautious. A single aspirin a day, whether
it is an 81 mg “baby” aspirin or a full-strength
325 mg aspirin will not thin the blood enough to
cause problems. I take Arches Tinnitus Relief Formula,
containing Ginkgo biloba, vitamin E and fish oil
every day with no bleeding issues.
The key word here is moderation.
Last summer I was doing some intense recreating
and developed very sore muscles in my legs and my
lower back. I cannot take ibuprofen because it sends
my tinnitus through the roof. Acetaminophen is liver
poison as far as I am concerned. So I began to take
3 aspirins daily, along with my regular supplements.
I continued for 3-4 days then stopped. The next
evening I developed a nosebleed that would not stop
and had to go to the emergency room. A couple of
inhalations of Afrin was all it took to stop it
(Afrin is a vasoconstrictor) but I learned my lesson.
Be aware and moderate in using combinations of ingredients
that can thin the blood.