Lightheadedness Symptoms, Causes & Common Questions
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Understand your lightheadedness symptoms, including 8 causes & common questions.
Feeling "lightheaded" is a general term that means you feel close to passing out. The sensation can be unnerving, but actually serves to stop you from overexerting yourself or otherwise trying to do things your body isn't prepared to do right then. Feeling lightheaded forces you to stop, rest, and reconsider before you push yourself too far.
You might hear this condition being called dizziness, or vertigo, but that is actually a different thing and means you feel as though your surroundings are spinning.
Actual lightheadedness may also be called orthostatic hypotension, postural hypotension, disequilibrium, or pre-syncope (syncope means "fainting").
Common characteristics of lightheadedness
If you're experiencing lightheadedness, it can likely be described by:
- The sensation that you cannot focus your thoughts or entirely control your movements
- Feeling as though you are about to pass out
- "Graying out": Or the fading of your peripheral vision
Who is most often affected by lightheadedness?
The following individuals are more often affected by lightheadedness:
- Older adults often experience lightheadedness: Almost every elderly person will have some degree of orthostatic hypotension, which means you feel lightheaded upon standing up.
- The risk is generally greater for anyone who: Becomes dehydrated, either through sweating or vomiting; has a drop in blood sugar, either from vomiting, medication, or simply not eating; or has a drop in blood pressure, especially from medications meant to lower blood pressure or remove fluid from the body (diuretics).
When is lightheadedness most likely to occur?
Lightheadedness is more likely when:
- You stand up quickly after sitting or lying down: Your body's mechanism to adjust blood pressure does not work correctly or quickly enough.
- You are sweating heavily during hot weather or exertion
- You have any illness that has caused vomiting, with resultant dehydration and low blood sugar
- Within an hour of eating a meal: Especially in an elderly person
Is lightheadedness serious?
Lightheadedness may vary in severity depending on the cause:
- Not serious: Some causes, such as dehydration or low blood sugar, are easily remedied and not serious as long as they are addressed.
- Moderately serious: Even moderate lightheadedness can lead to fainting and/or falling, which can cause serious injury.
- Serious: Lightheadedness can be a serious symptom if it occurs following a head injury, recurs frequently, or is accompanied by signs of stroke or heart attack.
Many conditions can have lightheadedness as a symptom. The most common are those involving dehydration, blood sugar, and blood pressure, as well as more serious causes such as a stroke or heart disease.
Most common causes
The most common reasons for lightheadedness include the following:
- Simple dehydration: This causes your blood volume to be reduced and your blood pressure to drop.
- Low blood sugar: This means there may not be enough energy available for the brain to function normally.
- Going suddenly from very hot to very cold conditions: Or vice versa, which makes it nearly impossible for the body to adjust quickly enough.
- Fainting or vasovagal syncope: Also known as neurocardiogenic syncope, this is a reaction to certain triggers that cause the heart rate and blood pressure to fall. Examples of these triggers are emotional distress, seeing blood, or severe pain.
Less common causes
Less common causes of lightheadedness may include the following:
- Orthostatic/postural hypotension: More likely in older adults, this means that you feel lightheaded and dizzy when you go from sitting to standing. This can simply be the result of aging, when the autonomic nervous system does not respond as quickly when you stand up, or it can be a side effect of medication.
- Emotional causes: Such as a panic attack, which leads to hyperventilation.
The following, although less common, are very serious causes of lightheadedness:
- Heart attack or significant changes in heart rate or rhythm (arrhythmia): These events significantly disrupt circulation and can have lightheadedness as one of the first symptoms.
- Stroke: This also interrupts normal circulation and significantly interferes with normal brain function — often starting with lightheadedness.
Feeling dizzy is never really normal unless it's from deliberate spinning, as with amusement park rides. The cause is rarely serious, but should be investigated as ongoing dizziness interferes with quality of life.
"Normal" dizziness – meaning it is not caused by a serious medical condition – may be due to:
- Binge drinking or recreational drug use.
- Low blood sugar.
- Panic attacks and hyperventilating.
- Pregnancy, when the growing fetus interferes with circulation.
- Menopause, when hormonal changes and hot flashes affect circulation.
- Postural hypotension, when blood pressure drops upon sitting up or standing.
Symptoms include feeling lightheaded or off-balance; a sensation of spinning; and sometimes nausea and vomiting.
Any dizziness can cause a fall with serious injury and will affect activities of daily living. A medical provider can determine the cause and offer solutions.
Diagnosis is made through patient history, physical examination, simple neurological tests, and sometimes blood tests and heart monitoring.
Dizziness sometimes clears up on its own after a short time. Further treatment involves adjusting medications and making lifestyle improvements, if needed.
Top Symptoms: dizziness, lightheadedness
Symptoms that always occur with normal dizziness: dizziness
Symptoms that never occur with normal dizziness: vertigo (extreme dizziness), racing heart beat
Urgency: Phone call or in-person visit
Dehydration means the body does not have enough water to carry out its normal processes.
Most susceptible to serious dehydration are young children with fever, vomiting, and diarrhea. In adults, some medications increase urination and can lead to dehydration. Anyone exercising vigorously, especially in hot weather, can quickly become dehydrated.
Symptoms include extreme thirst; dry mouth; infrequent, dark-colored urine; dizziness; and confusion. Young children may have sunken eyes, cheeks, and soft spot on top of the skull.
Severe dehydration is a serious medical emergency that can lead to heat stroke, kidney damage, seizures, coma, and death. Take the patient to the emergency room or call 9-1-1.
Diagnosis is made through blood tests and urine tests.
Mild dehydration can be treated simply by drinking extra water, or water with electrolytes such as sports drinks. More serious cases may be hospitalized for intravenous fluids.
It's important for anyone who is outside in hot weather, or who is ill, to drink extra fluids even before feeling thirsty as thirst is not always a reliable guide.
Top Symptoms: fatigue, dizziness, vomiting or diarrhea, racing heart beat, being severely ill
Urgency: Hospital emergency room
Hyperventilation syndrome is a type of anxiety or panic attack, where the primary symptom is fast, shallow breathing that leads to a drop in carbon dioxide levels in the blood. This drops changes the body chemistry and causes the discomfort.
Any sort of fear or excitement that might provoke an anxiety attack can bring on hyperventilation syndrome.
Symptoms are worse in some patients than in others, but include anxiety; lightheadedness; pain and constriction in the chest; numbness and tingling of the extremities; and a feeling of suffocation.
It is important to seek treatment for hyperventilation syndrome, because the symptoms can be debilitating and interfere with quality of life.
Diagnosis is made through detailed patient history, as well as a complete physical examination and lab tests to rule out any other conditions.
Treatment involves showing that patient that, during an anxiety attack, simply breathing into a paper bag for a few minutes will ease the symptoms and allow recovery. Psychological counseling, with an emphasis on managing stress, is also helpful.
Top Symptoms: anxiety, shortness of breath, dizziness, racing heart beat, chest pain
Symptoms that always occur with hyperventilation syndrome: rapid, deep breaths
Symptoms that never occur with hyperventilation syndrome: shortness of breath after a few stairs
Urgency: Primary care doctor
Stroke or tia (transient ischemic attack)
Transient ischemic attack, or TIA, is sometimes called a "mini stroke" or a "warning stroke." Any stroke means that blood flow somewhere in the brain has been blocked by a clot.
Risk factors include smoking, obesity, and cardiovascular disease, though anyone can experience a TIA.
Symptoms are "transient," meaning they come and go within minutes because the clot dissolves or moves on its own. Stroke symptoms include weakness, numbness, and paralysis on one side of the face and/or body; slurred speech; abnormal vision; and sudden, severe headache.
A TIA does not cause permanent damage because it is over quickly. However, the patient must get treatment because a TIA is a warning that a more damaging stroke is likely to occur. Take the patient to the emergency room or call 9-1-1.
Diagnosis is made through patient history; physical examination; CT scan or MRI; and electrocardiogram.
Treatment includes anticoagulant medication to prevent further clots. Surgery to clear some of the arteries may also be recommended.
Top Symptoms: dizziness, leg numbness, arm numbness, new headache, stiff neck
Symptoms that never occur with stroke or tia (transient ischemic attack): bilateral weakness
Urgency: Emergency medical service
Iron deficiency anemia
Iron deficiency anemia is a condition in which the body does not have enough iron to form hemoglobin, the protein in red blood cells that carries oxygen throughout the body.
The condition can be caused by acute blood loss through injury, surgery, or childbirth;chronic b...
Vasovagal syncope is sudden fainting caused by a sudden drop in heart rate and blood pressure when your body overreacts to certain emotional or neurologic triggers. A loss of consciousness occurs due to reduced blood flow to the brain.
Those with vasovagal syncope will also experienc...
Hypertrophic cardiomyopathy (HCM) means "abnormal thickening of the heart muscle." This can interfere with the heart's ability to pump blood.
Most often, an inherited genetic mutation causes HCM. However, aging, high blood pressure, diabetes, or thyroid disease can sometimes bring it about.
Many people have no symptoms at all. Some have unexplained chest pain, shortness of breath, fainting, or the feeling of rapid, fluttering heartbeat, because the abnormally thick heart muscle interferes with normal heartbeat and causes an arrhythmia. Take the patient to the emergency room or call 9-1-1.
Untreated hypertrophic cardiomyopathy can lead to serious heart disease and even sudden cardiac arrest and death, especially in people under age 30.
Diagnosis is made through echocardiogram; electrocardiogram; treadmill stress test; and/or cardiac MRI.
Treatment involves medication to relax the enlarged heart muscle and slow the rapid pulse. Surgery to remove some of the thickened muscle may be done, or a defibrillator may be implanted.
Anyone with a family history of HCM should ask their medical provider about screening for the disease, which involves regular echocardiography.
Top Symptoms: fatigue, shortness of breath, dizziness, racing heart beat, shortness of breath on exertion
Urgency: Primary care doctor
Orthostatic syncope (fainting)
Orthostatic syncope refers to a type of loss of consciousness caused by rapidly standing up from a sitting position, and not enough blood reaches the head. This can cause a person to pass out, but then come back to consciousness without lasting effects.
Top Symptoms: lightheadedness, brief fainting episode, dizziness and lightheadedness before passing out, fainting after standing up, fainting for the first time
Symptoms that always occur with orthostatic syncope (fainting): brief fainting episode, fainting after standing up
Urgency: Phone call or in-person visit
Lightheadedness treatments and relief
When lightheadedness is an emergency
Seek immediate treatment in the emergency room or call 911 if you experience lightheadedness along with:
- Chest pain
- Shortness of breath
- Pain in your arm, jaw, or back
- Sudden severe headache
- Difficulty walking or talking
When to see a doctor for lightheadedness
You should schedule an appointment for:
- Lightheadedness with a new medication: Episodes of lightheadedness that begin soon after you start a new medication
- Recurrent lightheadedness: Episodes of lightheadedness that recur and seem to have no specific cause
At-home treatments for lightheadedness
Remedies that you can try at home include the following:
- Lie down with your feet up
- Drink water or juice: Try a glass of water for rehydration. If you don't feel better soon, have a glass of orange juice to raise blood sugar if it is low. Symptoms should clear within 15 minutes. If they do not, you should seek medical attention right away.
- Always transition slowly from sitting to standing
- Wear support stockings
- Drink plenty of fluids, but avoid alcohol: Alcohol is dehydrating
- Use small doses of caffeine throughout the day: It tends to keep blood pressure from dropping.
- Keep cool: Hot baths and otherwise high temperatures cause blood vessels to dilate and blood pressure to drop, inducing lightheadedness.
FAQs about lightheadedness
Here are some frequently asked questions about lightheadedness.
Will dehydration cause lightheadedness?
Yes, moderate to severe dehydration can cause lightheadedness. If you do not have sufficient blood volume, which can be caused by not drinking enough to replace liquid lost to sweat and urine, it can be challenging for your body to pump blood with adequate pressure up to your brain. This lack of sufficient blood flow, especially when standing, can cause lightheadedness.
Why do I feel lightheaded when I stand up?
You can feel lightheaded when you stand up if you have not had adequate hydration, are bleeding, or have been lying down for a long time and suddenly stand up. Your body has to increase blood pressure by pumping harder and constricting blood vessels to provide adequate blood flow to the brain.
Why does anxiety cause lightheadedness?
Anxiety can cause lightheadedness through a variety of mechanisms, most notably though severe hyperventilation which lowers the carbon dioxide (CO2) in the blood, which can cause tingling in the fingertips and mild lightheadedness. Additionally, a fear response can cause a vasovagal reaction which can lead to lightheadedness and even fainting by both slowing the heart rate and vasodilation.
Can lightheadedness be a sign of low blood pressure?
Yes, lightheadedness is often a sign of low blood pressure (hypotension). The low blood pressure causing lightheadedness can be caused by a variety of illnesses or medications. Shock, surprise, or anxiety can cause a sudden dilation of blood vessels in the body lowering blood pressure, which can cause fainting.
What are the differences between dizziness and lightheadedness?
Dizziness is a condition in which one's equilibrium is upset. This can occur when an individual is unable to catch their balance, as is often the case when someone consumes excessive amounts of alcohol or feel the room may be spinning around them. If it is an inner ear canal problem, this may lead to a diagnosis of vertigo. Lightheadedness is more so a feeling of confusion or inability to focus on a particular item and often described as near-fainting. Vision may change, one may feel weak in the knees, and, generally, the room will not be spinning. Many people use the terms dizziness and lightheadiness interchangeably and why it is important to be more descriptive when discussing with your healthcare provider.
Questions your doctor may ask about lightheadedness
- Have you been feeling more tired than usual, lethargic or fatigued despite sleeping a normal amount?
- Did you faint?
- Do you notice your heart beating hard, rapidly, or irregularly (also called palpitations)?
- Have you experienced any nausea?
Self-diagnose with our free Buoy Assistant if you answer yes on any of these questions.
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- Blahd Jr WH, Husney A, Romito K. Dizziness: Lightheadedness and Vertigo. University of Michigan: Michigan Medicine. Updated September 23, 2018. UofM Health Link.
- Can You Recognize a Heart Attack or Stroke? NIH News in Health. Published August 2014. News in Health Link.
- Lightheaded? Top 5 Reasons You Might Feel Woozy. Harvard Medical School: Harvard Health Publishing. Updated August 13, 2018. Harvard Health Publishing Link.