Syncope, or fainting, is a sudden loss of consciousness caused by decreased
blood flow to the brain. Recovery occurs within seconds or minutes for many
causes of fainting. Approximately 3 to 4 percent of people, mostly the elderly,
experience episodes of fainting.
|Signs and Symptoms|
You may experience the following signs and symptoms before you
- Blurred vision
- Heaviness in your lower limbs
- Nausea, and sometimes vomiting
During a fainting episode, in addition to loss of consciousness, you may
experience the following symptoms:
- Abnormal paleness
- Falling down if standing, slumping if seated
- Spasmodic jerks of your body
- Weak pulse
- Drop in blood pressure
|What Causes It?|
Fainting often occurs from a simple, non-medical cause, but may be the result
of a serious health condition, such as heart disease (decreased blood flow to
the heart and/or irregular heart rhythm), low blood sugar (often related to
diabetes), seizures, panic attacks, and problems regulating blood pressure.
|Who's Most At Risk?|
People with the following conditions or characteristics are at risk for
- Over 65 years of age
- Preexisting heart disease
- Recreational drug use
- Taking certain medications such as antihypertensives, insulin, oral
hypoglycemics, diuretics, antiarrhythmics, or anticoagulants
|What to Expect at Your Provider's Office|
If you have fainted, you should see your healthcare provider. He or she will
ask questions, do a physical examination, and perform diagnostic tests, which
may include blood tests, electrocardiogram (ECG), and imaging of the brain, such
as magnetic resonance imaging (MRI). Your provider will focus on symptoms
associated with the current fainting episode, medications you take, preexisting
medical conditions, and your description of any similar episodes you may have
experienced in the past. This will help your provider pinpoint the cause of the
fainting episodes and identify or rule out particular health conditions. If
seizures are suspected, he or she may perform a test called an
Some cases of fainting may be preventable, depending on the
- Avoid fatigue, hunger, and stress.
- Avoid changing positions quickly, especially rising from a sitting or
lying-down position, for fainting caused by a change in blood pressure due to a
sudden change in position. Sleep with the head of your bed elevated; wear
elastic stockings to prevent pooling of blood in your lower legs; avoid standing
for long periods; avoid diuretics and other medicines that can contribute to the
problem (your healthcare provider can help you identify these
- Avoid tight clothing around the neck for fainting caused by a rise in
blood pressure. Turn the whole body and not just the head when looking
- Avoid standing still for long periods for fainting that happens often.
To prevent injuries, cover floors with thick carpeting and avoid driving or
operating mechanical equipment.
- Avoid caffeine and alcohol.
Any serious underlying health condition must be treated. At the time of the
fainting episode, place the person in a position that increases blood flow to
the brain (such as elevating the legs so that blood flows with gravity back
toward the head). A pregnant woman should lie on her left side to relieve
pressure on the aorta, the largest blood vessel in the body. Loosen all tight
clothing, apply cold water to the person's face, and turn the person's head to
the side to prevent vomiting or choking.
When irregular heart rhythm causes fainting, your healthcare provider may
prescribe medications such as beta-blockers, after some tests.
Mineralocorticoids (such as fludrocortisone), a substance involved in regulating
the balance of salt and water in the body, or salt tablets may be prescribed in
the case of decreased circulation of blood or pooling of blood in the
|Surgical and Other Procedures|
In some cases where fainting is caused by an underlying heart condition, such
as slow or rapid heartbeat, a cardiac pacemaker may be
|Complementary and Alternative Therapies|
You may experience warning signs before fainting. Autogenic training (a
hypnosis-based healing method that consists of a series of mental exercises
designed to relax the individual and to relieve suppressed anger, emotion, and
tension), deep breathing, relaxation techniques, and biofeedback may help you
become aware of pre-fainting symptoms to avoid fainting. These techniques may
also help you control fainting related to nervous system regulation of your
blood pressure. Nutrition, herbs, and acupuncture may help treat fainting; see
following sections for more details.
As stated earlier, low blood sugar sometimes plays a role in fainting,
particularly in combination with low blood pressure. Therefore, if you are prone
to fainting for this reason, make sure you eat the appropriate amount and type
of calories. This is especially important if you are elderly or have a history
of fainting. If your body has trouble processing sugar (as in the case of
diabetes), you may need to avoid refined foods and sugar, and eat small,
frequent meals high in protein. It is best to consult a registered dietitian to
determine the right nutritional program for your specific needs.
In a case report about one 38-year-old man, licorice root (Glycyrrhiza
glabra) combined with a high-salt diet helped clear up fainting due to low
blood pressure and nervous system problems. However, you should not use licorice
root if you have high blood pressure, low levels of potassium, severe kidney
disease, or if you are pregnant. Even if you have normal blood pressure, a
healthcare provider should monitor you if you take licorice.
Some herbs, used alone and together, may help protect your heart. For
instance, hawthorn (Crataegus monogyna) may help maintain blood pressure,
control blood flow through the heart, and treat irregular heartbeat. Many herbs,
however, can have toxic effects on your heart if not used correctly, and may
cause fainting or more serious problems. Use herbal therapies only under the
supervision of an experienced healthcare provider.
No scientific literature supports the use of homeopathy for fainting
specifically. But an experienced and certified homeopath may assess your
individual constitution and symptoms, and then recommend one of the following
remedies for fainting or pre-fainting symptoms:
- Carbo vegetabilis for fainting or lightheadedness after rising
in the morning, from loss of fluids, or from becoming overheated
- Opium for fainting due to excitement or fright
- Sepia for fainting following prolonged standing, exercise, or
fluid loss due to fever
Acupuncture may be helpful in treating syncope. A clinical analysis of 102
serious cases of loss of consciousness, including 87 semi-comatose and 15
comatose patients, reviewed the use of acupuncture and moxibustion (burning
herbs over the skin) to revive people who could not be revived with traditional
Chinese or Western drugs. Seventy-eight patients had either excellent or good
results (they were conscious, pulse was normal or nearly normal and stable, and
drug treatment was at least partially halted during the procedure). Three
patients had fair results (they were conscious, blood pressure was nearly normal
but not stable, and pulse was scattered and weak). The treatment failed in the
remaining 21 patients, who were unable to be resuscitated from coma and died
after all treatments—including Western and
Acupuncture is known for rarely causing side effects or complications. But
some patients faint during acupuncture treatments. Called "needle fainting" in
Chinese medicine, this comes from lowered blood pressure. It is not considered a
serious complication of acupuncture. Needle fainting may be easily remedied or
prevented by changing the positions of the patient and the
In most people, simple fainting is not a sign of a life-threatening disease,
particularly if it only happens once. The elderly are at increased risk for
injury after a fainting episode, especially from fractures.
Many people with syncope, especially the elderly and those with preexisting
heart disease, may be hospitalized to look for a cause. Continuous ECG
monitoring can identify irregular heartbeat as a cause of fainting, especially
in people who have recurring fainting episodes.
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|Review Date: October 2000|
|Reviewed By: Participants in the review process include: Shiva Barton, ND, Wellspace,
Cambridge, MA; Jacqueline A. Hart, MD, Department of Internal Medicine,
Newton-Wellesley Hospital, Harvard University and Senior Medical Editor
Integrative Medicine, Boston, MA; David Winston, Herbalist, Herbalist and
Alchemist, Inc., Washington, NJ.|
Copyright © 2004 A.D.A.M., Inc
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