Dizziness is lightheadedness, feeling like you might faint, being unsteady, loss of balance, or vertigo (a feeling that you or the room is spinning or moving).

Most causes of dizziness are not serious and either quickly resolve on their own or are easily treated.

Lightheadedness happens when there is not enough blood getting to the brain. This can happen if there is a sudden drop in your blood pressure or you are dehydrated from vomiting, diarrhea, fever, or other causes. Many people, especially as they get older, experience lightheadedness if they get up too quickly from a lying or seated position. Lightheadedness often accompanies the flu, hypoglycemia, common cold, or allergies.

More serious conditions that can lead to lightheadedness include heart problems (such as abnormal heart rhythm or heart attack), stroke, and severe drop in blood pressure (shock). If any of these serious disorders is present, you will usually have additional symptoms like chest pain, a feeling of a racing heart, loss of speech, change in vision, or other symptoms.

The most common causes of vertigo are benign positional vertigo and labyrinthitis. Benign positional vertigo is vertigo that happens when you change the position of your head. Labyrinthitis usually follows a cold or flu and is caused by a viral infection of the inner ear. Meniere's disease is another common inner ear problem. It causes vertigo, loss of balance, and ringing in the ears.

Much less commonly, vertigo or feeling unsteady is a sign of stroke, multiple sclerosis, seizures, a brain tumor, or a bleed in your brain. In such conditions, other symptoms usually accompany the vertigo or imbalance.

If you tend to get lightheaded when you stand up, avoid sudden changes in posture.

If you are thirsty or lightheaded, drink fluids. If you are unable to keep fluids down from nausea or vomiting, you may need intravenous fluids. These are delivered to you at the hospital.

Most times, benign positional vertigo and labyrinthitis go away on their own within a few weeks. During attacks of vertigo from any cause, try to rest and lie still. Avoid sudden changes in your position as well as bright lights. Be cautious about driving or using machinery.

Some vertigo can be reduced by working with a physical therapist. Medications from your doctor may help you feel better.

Such medications include antihistamines, sedatives, or pills for nausea. For Meniere's disease, surgery may be necessary.

Call 911 or go to an emergency room if someone with dizziness also has:

• A head injury
• Fever over 101°F, headache, or very stiff neck
• Convulsions or ongoing vomiting
• Chest pain, heart palpitations, shortness of breath, weakness, inability to move an arm or leg, or change in vision or speech
• Fainting and losing consciousness for more than a few minutes

Call your doctor if:

• You have never had dizziness before.
• Symptoms you have had in the past are different (for example, last longer than usual, are worse than before, or are interfering with your daily activities).
• Medication is the suspected cause. Talk to your health care provider before making any changes to your medication.
• You have any hearing loss.

Your doctor will perform a physical exam, focusing on your heart, head, ears, and nervous system, and ask question such as:

• Does your dizziness feel like lightheadedness, vertigo, or imbalance?
• Does your dizziness occur with a change in body position?
• What other symptoms occur when you feel dizzy?
• When did your dizziness begin?
• Are you always dizzy or does the dizziness come and go?
• How long does the dizziness last (minutes, hours)?
• Did another illness develop before or after the dizziness began? How much later?
• Have you had any nausea and vomiting?
• Do you have a significant amount of stress or anxiety?

• Blood pressure measurements and tests
• ECG
• Hearing tests
• Neurological tests
• Balance testing (ENG) may be required.
• MRI

Promptly treat ear infections, colds, flus, sinus congestion, and other respiratory infections. This may help prevent labyrinthitis and Meniere's disease.

If you have a cold, the flu, or other viral illness, drink plenty of fluids to prevent getting dehydrated.

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Swartz R. Treatment of vertigo. Am Fam Physician. 2005; 71(6): 1115-1122.