Lightheadedness is the feeling that you may faint, but you do not. Your heartbeat may be fast or feel like it flutters.You might say you’re dizzy if the room feels like it is spinning or you have trouble keeping your balance. You might say you’re lightheaded when you feel faint or like you’re about to pass out. Or you might use the words interchangeably. They can mean different things to different people. Dizziness and lightheadedness aren’t always a cause for worry. But they sometimes can be a sign of a serious health problem. Lightheadedness may occur when you take certain medicines, such as medicine to lower your blood pressure. Dehydration, low sodium, low blood sugar, an abnormal heart rhythm, and anxiety are other common causes.

Low Blood Sugar

Sugar is a fuel for your body. Too little of it in your bloodstream, called hypoglycemia, usually is linked to diabetes or its treatment. It also can happen if you’re on the intermittent fasting diet or from other causes. You might feel faint and confused. Your vision might be blurry. A few grams of carbs like fruit juice, candy, or glucose tablets usually can restore your blood sugar levels quickly. Otherwise, you could pass out.


It’s not a fear of heights, as lots of people believe. Vertigo isn’t really an illness. Instead, it’s a symptom. You feel as if you or the space around you is spinning. You also may feel faint, unbalanced, or sick to your stomach. The most common type of vertigo, peripheral vertigo, happens when you have inner ear problems that affect your balance.

Standing Up Too Quickly

The medical name for this is orthostatic hypotension, also known as postural hypotension. When you rise from sitting or lying down, blood may not reach your brain fast enough. You might feel lightheaded or dizzy. The feeling should pass in a few minutes. If not, it could be a sign that something more serious may be wrong.


Some hypertension, heart, and antidepressant drugs can drop your blood pressure and make you woozy. Insulin and some other drugs to lower blood sugar in people with diabetes may work too well and cause the same problem. Dizziness also can be a common problem if you’re older and take multiple medications. Tell your doctor if you feel unsteady or unbalanced after you start new meds.

Motion Sickness

Traveling by ship, car, plane, or train can confuse your brain about your body’s movement. You might feel like throwing up or break out in cold sweats. Sometimes, seasickness after a cruise can turn into “land sickness.” The disorder is called mal de debarquement. The swaying, rocking, unsteady sensations can last for weeks or longer. Researchers think the problem may stem from your brain, not your inner ears. 


This can happen if you don’t drink enough fluids to replace what you lose through sweat or pee. That can lower your blood pressure and make it harder for your nervous system to control it. You might feel parched, tired, and lightheaded. If your pee is yellow instead of clear, it’s a sign you should sip a bit more.

Meniere’s Syndrome

This illness can trigger a dizzy spell that lasts from 20 minutes to several hours. Often, you may be nauseous and vomit. Your ears might feel full and it may be hard to hear. You also may have ringing in the ear (tinnitus). Doctors don’t know what causes Meniere’s Syndrome. Medication, cutting salt or other diet changes, and physical therapy may help.

Perilymph Fistula

Trauma such as a hit to the head can tear the tissue that separates the air-filled middle ear from the fluid-filled inner ear. This can cause dizziness and balance problems. Your ear may ring, or feel full and sensitive to loud noises. Changes in air pressure, as in an airplane or elevator, can worsen it. A couple of weeks of rest may be all you need for the hole to heal. But you may need surgery if your problem doesn’t go away.

Low Iron

Your body relies on iron from foods like meat, tofu, and spinach to help red blood cells pump enough oxygen around your body. Lack of this mineral is called anemia. It can leave you dizzy, weak, pale, and turn your hands cold.  Heavy menstrual periods also can lead to anemia.

Heart Problems

Weakened cardiac muscle (heart failure), gummed up blood vessels (coronary heart disease), and similar heart issues can deprive your brain of oxygen-rich blood. That could make you dizzy and lightheaded enough to faint. It can start without warning, and happen again and again for weeks. See your doctor for any dizziness or if you have chest pain, irregular heartbeat, tiredness, or other symptoms.

Vestibular Neuritis

Your vestibular nerve connects your inner ear to the brain. A viral infection can swell the nerve suddenly. It might make you woozy, unsteady, and sick to your stomach. The episode may last a few hours or days. But you may need a month or more to recover fully. When it affects hearing as well, it’s called labyrinthitis. It usually clears up on its own, but you may need to rest in bed if your symptoms are bad.

Other Causes

If you’re suddenly lightheaded, it could signal an emergency like a clot in your blood or a burst blood vessel (stroke or aneurysm). Call 911 if you:

  • Can’t move or feel your arms or one side of the face
  • Can’t see out of one or both eyes 
  • Start to slur or garble your speech 
  • Get a sudden painful headache



Return to the emergency department if:

  • You have sudden chest pain.
  • You have trouble breathing or shortness of breath.
  • You have vision changes, are sweating, and have nausea while you are sitting or lying down.
  • You feel flushed and your heart is fluttering.
  • You faint.

Contact your healthcare provider if:

  • You feel lightheaded often.
  • Your heart beats faster or slower than usual.
  • You have questions or concerns about your condition or care.

Follow up with your healthcare provider as directed:

You may need more tests to help find the cause of your lightheadedness. The tests will help healthcare providers plan the best treatment for you. Write down your questions so you remember to ask them during your visits.


Talk with your healthcare provider about these and other ways to manage your symptoms:

  • Lie down when you feel lightheaded, your throat gets tight, or your vision changes. Raise your legs above the level of your heart.
  • Stand up slowly. Sit on the side of the bed or couch for a few minutes before you stand up.
  • Take slow, deep breaths when you feel lightheaded. This can help decrease the feeling that you might faint.
  • Ask if you need to avoid hot baths and saunas. These may make your symptoms worse.

Watch for signs of low blood sugar:

These include hunger, nervousness, sweating, and fast or fluttery heartbeats. Talk with your healthcare provider about ways to keep your blood sugar level steady.

Check your blood pressure often:

You should do this especially if you take medicine to lower your blood pressure. Check your blood pressure when you are lying down and when you are standing. Ask how often to check during the day. Keep a record of your blood pressure numbers. Your healthcare provider may use the record to help plan your treatment.

Keep a record of your lightheadedness episodes:

Include your symptoms and your activity before and after the episode. The record can help your healthcare provider find the cause of your lightheadedness and help you manage episodes.