Condition Basics

What is Bell's palsy?

Bell's palsy is a paralysis or weakness of the muscles on one side of your face. Damage to the facial nerve that controls muscles on one side of the face causes that side of your face to droop. The nerve damage may also affect your sense of taste and how you make tears and saliva. This condition comes on suddenly, often overnight, and usually gets better on its own within a few weeks.

Bell's palsy is not the result of a stroke or a transient ischemic attack (TIA). While stroke and TIA can cause facial paralysis, there is no link between Bell's palsy and either of these conditions. But sudden weakness that occurs on one side of your face should be checked by a doctor right away to rule out these more serious causes.

What causes it?

The cause of Bell's palsy is not clear. Most cases are thought to be caused by the herpes virus that causes cold sores.

In most cases of Bell's palsy, the nerve that controls muscles on one side of the face is damaged by inflammation.

Many health problems can cause weakness or paralysis of the face. If a specific reason cannot be found for the weakness, the condition is called Bell's palsy.

What are the symptoms?

Symptoms of Bell's palsy include:

• Sudden weakness or paralysis on one side of your face that causes it to droop. This is the main symptom. It may make it hard for you to close your eye on that side of your face.
• Drooling.
• Eye problems, such as excessive tearing or a dry eye.
• Loss of ability to taste.
• Pain in or behind your ear.
• Numbness in the affected side of your face.
• Increased sensitivity to sound.

How is it diagnosed?

Your doctor may diagnose Bell's palsy by asking you questions, such as about how your symptoms developed. He or she will also give you a physical and neurological exam to check facial nerve function.

If the cause of your symptoms is not clear, you may need other tests, such as blood tests, an MRI, or a CT scan.

How is Bell's palsy treated?

Most people who have Bell's palsy recover completely, without treatment, in 1 to 2 months. ^{footnote 1}This is especially true for people who can still partly move their facial muscles. But a small number of people may have permanent muscle weakness or other problems on the affected side of the face.

Treatment with corticosteroid medicines (such as prednisone) can make it more likely that you will regain all facial movement. They work best if they are taken soon after symptoms start (within 3 days). Sometimes antiviral medicines (such as acyclovir) may be added to corticosteroid medicines to treat Bell's palsy. But evidence for using antiviral medicines is weak. They may help in some cases, but in general they do not affect recovery. ^{footnote 2}

Some people may not be able to take corticosteroid medicines because of other health problems. It's important to remember that most people with Bell's palsy recover completely without any treatment.

How can you care for yourself?

Facial exercises

As the nerve in your face begins to work again, doing simple exercises-such as tightening and relaxing your facial muscles-may make those muscles stronger and help you recover more quickly. Massaging your forehead, cheeks, and lips with oil or cream may also help.

Eye care

If you can't blink or close your eye fully, your eye may become dry. A dry eye can lead to sores and serious vision problems. To help protect the eye and keep it moist:

• Use your finger to close and open your eyelid often throughout the day.
• Use eyedrops ("artificial tears") or ointment. Those that contain methylcellulose are a good choice and don't require a prescription. You may want to use drops during the day and ointment at night while you sleep. Ask your doctor how often to use the drops.
• Wear an eye patch while you sleep, and wear glasses or goggles the rest of the time.

Mouth care

If you have no feeling and little saliva on one side of your tongue, food may get stuck there, leading to gum disease or tooth decay. Brush and floss your teeth often and well to help prevent these problems. To prevent swallowing problems, eat slowly and chew your food well. Eating soft, smooth foods, such as yogurt, may also help.