Syncope is the medical term for fainting. It happens when your brain doesn't get enough blood flow and you lose consciousness. Usually a slow heart rate causes a drop in blood pressure, which reduces blood flow to the brain. In most cases, you recover within seconds or minutes. A small number of people, mostly the elderly, have episodes of fainting.
If you have slurred speech, or have trouble moving an arm or a leg after fainting, call for emergency help right away. This may be a sign of stroke.
Signs and Symptoms
Signs and symptoms that you might have before you faint include:
- Feeling warm
- Blurred vision
- Heaviness in your legs
- Nausea and sometimes vomiting
In addition to losing consciousness when you faint, you may also:
- Turn very pale
- Fall down or slump
- Have spasmodic jerks of your body
- Have a weak pulse
- Experience a drop in your blood pressure
What Causes It?
Fainting often happens due to a simple, non medical cause, such as:
- Standing up for long periods of time
- Feeling emotionally distressed
- Seeing something upsetting or disturbing, such as at the sight of blood
Rarely, it may be the result of a health condition, such as:
- Heart disease (decreased blood flow to the heart or irregular heart rhythm)
- Low blood sugar
- Panic attack
- Problems regulating blood pressure
- Severe blood loss
Who Is Most At Risk?
Certain conditions or characteristics may put you at risk for fainting, such as:
- Being over 65 years of age
- Having heart disease, diabetes, or high blood pressure
- Using recreational drugs
- Taking certain medications, such as blood pressure medication, insulin, oral diabetes medications, diuretics (water pills), medications to control heart rhythm, or blood thinners
What to Expect at Your Doctor's Office
You should see your doctor after fainting. Your doctor will:
- Ask questions about what you were doing before you fainted.
- Ask how you felt afterward.
- Do a physical exam.
- Conduct other tests, such as blood tests and electrocardiogram (ECG).
- Conduct imaging of the brain, such as magnetic resonance imaging (MRI).
- Focus on medications you take.
- Consider any pre-existing medical conditions you might have.
- Compare your most recent fainting spell with similar episodes you had in the past.
This will help your doctor pinpoint why you fainted and rule out certain health conditions. If seizures are suspected, your doctor may also do a test called an electroencephalogram (EEG).
To avoid fainting.
- Avoid fatigue, hunger, and stress. DO NOT skip meals.
- Drink plenty of fluids.
- Avoid changing positions quickly, especially when you get up from a sitting or lying down position.
- Sleep with the foot of your bed raised.
- DO NOT stand for long periods of time.
- Wear elastic stockings if needed to keep blood from pooling in your legs, which may reduce blood flow to the brain.
- Diuretics and other medicines (both prescription and non-prescription) can contribute to the problem. So check with your doctor.
- Avoid wearing anything tight around your neck.
- Turn your whole body, not just your head, when looking around.
- To prevent injuries, cover floors with thick carpeting, and avoid driving or using mechanical equipment.
- Avoid caffeine and alcohol.
If you feel like you are going to faint, lie down and raise your legs to keep blood flowing to your brain. If you can't lie down, sit down and put your head between your knees, stand with your legs crossed and thighs pressed together. This can also help keep blood from pooling in your legs.
Any serious underlying health condition should be treated. When a person faints:
- Raise the legs to help increase blood flow to the brain.
- Loosen any tight clothing.
- Apply cold water to the person's face.
- Turn the person's head to the side to prevent vomiting or choking.
A pregnant woman should lie on her left side to relieve pressure on the heart.
When an irregular heartbeat causes fainting, your doctor may prescribe medications such as beta-blockers or antiarrhythmics. Your doctor may also prescribe steroids (such as fludrocortisone) or salt tablets to help you control the amount of sodium and fluids in your body.
Surgical and Other Procedures
If fainting is caused by a heart condition, such as a slow or rapid heartbeat, you may need a pacemaker.
Complementary and Alternative Therapies
Although there are no specific treatments for fainting, a number of alternative therapies can help protect the heart and blood vessels. Fainting may be caused by a serious underlying health condition. So check with your doctor before taking any herbs or supplements. Always tell your doctor about the herbs and supplements you are using or considering using.
You may have warning signs before fainting. Hypnosis, deep breathing, relaxation techniques, and biofeedback may help you avoid fainting. These techniques may also help you control fainting related to regulation of your blood pressure.
Nutrition and Supplements
To stay healthy and avoid fainting:
- DO NOT skip meals. Eat a healthy diet, with plenty of fruits and vegetables, whole grains, healthy protein, and good fats.
- Avoid caffeine, alcohol, and tobacco.
- Drink plenty of fluids.
These supplements may promote heart health:
- Omega-3 fatty acids. Such as fish oil -- may help reduce inflammation and improve heart health. Cold-water fish, such as salmon or halibut, are good sources. Omega-3 fatty acids may increase the risk for bleeding, especially if you also take blood thinners, such as warfarin (Coumadin), clopidogrel (Plavix), or aspirin.
- Coenzyme Q10 (C0Q10). An antioxidant that may be good for heart health. DO NOT take CoQ10 if you take blood thinners, such as warfarin (Coumadin), clopidogrel (Plavix), or aspirin. CoQ10 can make these drugs less effective. So they might not work as well.
- Alpha-lipoic acid. An antioxidant that may be good for heart health. People who take thyroid hormone should ask their doctors before taking alpha-lipoic acid. People who have low levels of thiamine should not take alpha-lipoic acid.
- L-arginine. An antioxidant that may help promote good circulation. Be sure to ask your doctor before taking L-arginine because it may interfere with other treatments and may not be right for you. People who have a history of a heart attack, heart disease, low blood pressure, or circulatory issues should speak to their doctors before taking L-arginine. People who take medication for circulation, including medications for erectile dysfunction, should also take caution when taking L-arginine. It can also cause problems with blood pressure, as well as make herpes infections worse. Some people may be allergic to L-arginine.
The use of herbs is a time-honored approach to strengthening the body and treating disease. However, herbs can trigger side effects and interact with other herbs, supplements, or medications. For these reasons, take herbs with care and under the supervision of a health care provider.
- Green tea (Camelia sinensis). An antioxidant and anti-inflammatory that may be good for heart health. Use caffeine-free products. You may also make teas from the leaf of this herb.
- Bilberry ((Vaccinium myrtillus). An antioxidant that helps promote good circulation. Bilberry may increase the risk for bleeding, especially if you also take blood thinners, such as warfarin (Coumadin), clopidogrel (Plavix), or aspirin. People with low blood pressure, heart disease, diabetes, or blood clots should not take bilberry without first talking to their doctors. DO NOT take bilberry if you are pregnant or breastfeeding.
- Ginkgo (Ginkgo biloba). An antioxidant that may be good for heart health. Ginkgo interacts with many medications, including blood thinners, such as warfarin (Coumadin) and clopidogrel (Plavix). People with diabetes, fertility problems, a history of seizures, and bleeding disorders may not be able to take ginkgo. Because of the potential for many interactions, DO NOT take ginkgo without your doctor's supervision.
Sometimes, fainting may be due to drops in a hormone called cortisol. Ask your doctor about testing for low cortisol. Some doctors may prescribe cortisol hormone supplements or use nutrients and herbs to get cortisol levels back to normal.
Before prescribing a remedy, homeopaths take into account a person's constitutional type, includes your physical, emotional, and intellectual makeup. An experienced and certified homeopath will assess your individual constitution and symptoms, and then recommend remedies. Below are common remedies used for fainting or pre-fainting symptoms:
- Carbo vegetabilis. Used for fainting or lightheadedness after rising in the morning, from loss of fluids, or from becoming overheated.
- Opium. Used for fainting due to excitement or fright.
- Sepia. Used for fainting following prolonged standing, exercise, or fluid loss due to fever.
Acupuncture may help treat fainting. A clinical analysis of 102 serious cases of loss of consciousness reported that acupuncture helped in a large number of these cases.
Acupuncture does not often cause side effects or complications. Some people may faint during acupuncture treatments, although it is not considered a serious complication.
In most people, fainting is not a sign of a life-threatening disease, particularly if it only happens once. The elderly have a higher risk for injury after a fainting episode, especially from fractures. People who faint due to heart disease tend to have a poorer prognosis than those who have heart disease without fainting.
Many people who faint, especially the elderly and those who have heart disease, may be hospitalized to look for a cause. Continuous ECG monitoring can help spot an irregular heartbeat as a cause of fainting, especially in people who faint more than once.
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- Last reviewed on 11/19/2016
- Steven D. Ehrlich, NMD, Solutions Acupuncture, a private practice specializing in complementary and alternative medicine, Phoenix, AZ. Review provided by VeriMed Healthcare Network. Also reviewed by the A.D.A.M Editorial team.
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