Overview of Bell's Palsy

Bell's palsy is the most common cause of facial weakness. It is an impairment of the facial nerve, which is the nerve that controls facial movement. Bell’s palsy develops pretty quickly and it can be stressful and frightening due to the dramatic change in the appearance of the face, but it often improves on its own within a few months.

Bell's palsy typically worsens over the course of a few days before it stabilizes. It only affects one side of the face, and it can cause the whole entire side of your face to be weak, including your forehead, eyelid, cheek and mouth.

Bell’s palsy often impairs chewing, and you may notice that you drool, particularly when drinking water. Your speech can sound a bit slurred due to difficulty controlling the muscles of your mouth. It can cause dryness and even redness of the eye due to decreased blinking and diminished facial tears.

Bell's palsy might also cause some problems with your ability to taste food or to produce tears. Some people with Bell’s palsy experience ear pain along with the face weakness.

Residual Symptoms

Sometimes, after an episode of Bell's palsy is largely resolved, you might continue to experience slight weakness of your face lasting for years or you might experience mild tingling of your face lasting for months.

Bell's palsy is more common in adults than in children, and it is not a sign of any serious health problem. It is a peripheral neuropathy (nerve disease) of the facial nerve, which is the 7th cranial nerve. This nerve comes off the brain stem and controls facial movement.

Sometimes Bell's palsy is triggered by a virus, inflammation or stress. But most of the time, it is impossible to pinpoint the exact cause of the condition, and it is often considered idiopathic (without a known cause).

Much of the time, weakness of one side the face turns out to be Bell's palsy, but it is important for you to know that weakness of the face can be a stroke or another neurological condition. If one side of your face is weak, your doctor will examine you to check for causes of facial weakness, such as a stroke, a tumor, or an infection.

There are some physical characteristics of Bell's palsy that differentiate it from facial weakness caused by a problem in the brain. Bell's palsy causes weakness of the lower and upper parts of the face, while a lesion of the brain causes drooping of the mouth, decreased cheek movement, and trouble opening or closing your eyelid, usually with a normal or almost normal ability to move the forehead. So, while Bell's palsy is not as serious as facial weakness caused by a disorder in the brain, the facial weakness is usually more severe.

Associated Symptoms

When stroke causes weakness of one side of the face, there are usually other symptoms such as dizziness, headaches, or arm weakness, which should not accompany Bell's palsy. An infection typically causes a fever, and a tumor may cause other neurological signs along with the facial weakness.

Diagnostic Tests

A brain MRI or CT scan can usually identify a lesion in the brain if that is the cause of your facial weakness. But because Bell's palsy is a neuropathy, it is not associated with abnormalities on imaging tests of the brain.

Most of the time, Bell's palsy resolves on its own. There are medications that can help speed your recovery, such as anti-inflammatory steroids, which are occasionally used for persistent or severe situations.

You may need to use eye drops because your eye can become dry, red, or itchy. Some people use an eye patch at night to prevent irritation, but you can decide whether or not you want to use an eye patch based on your own level of eye comfort.

A Word From Verywell

If any part of your face becomes weak or droopy, you should see a doctor. Even if you look up your symptoms on the Internet or if a friend or family member tells you that you look like you have Bell's palsy, you should still make sure to get medical attention right away. Your symptoms could be caused by a variety of neurological conditions, and it is important to exclude serious causes.

The most important thing to keep in mind is that, while Bell's palsy is not a dangerous medical condition, you do need to seek professional medical attention to ensure an accurate diagnosis and to prevent serious irritation of your eye.