Bell's Palsy: Symptoms, Diagnosis & Treatment

Bell’s palsy causes temporary paralysis, or palsy, of facial muscles. It occurs when a condition, such as a viral infection, causes inflammation and swelling of the seventh cranial nerve (the nerve that controls facial muscles).

With Bell’s palsy, your face droops on one side or, rarely, both sides. You may have a lopsided smile, or an eyelid that won’t close. These effects typically last several months and go away without treatment. The condition gets its name from Sir Charles Bell, a Scottish surgeon who first described it during the 19th century.

Bell’s palsy

How common is Bell’s palsy?

About 40,000 people in the U.S. develop Bell’s palsy every year.

Who might have Bell’s palsy?

Bell’s palsy affects men and women equally. It typically occurs in people between the ages of 15 and 60. You may be more prone to Bell’s palsy if you are pregnant or have:

• Autoimmune disease.
• Diabetes.
• Family history of Bell’s palsy.
• Cold sores (herpes simplex virus).
• High blood pressure (hypertension).
• Mononucleosis (Epstein-Barr virus).
• Shingles (herpes zoster virus).

Can you get Bell’s palsy more than once?

It’s unusual to get Bell’s palsy more than once in a lifetime, but it can happen. A recurrence is most likely within two years of the first incident. The facial nerve palsy may affect the same side of your face or the opposite side. You’re more at risk for a recurrence if you have a family history of the disease.

What causes Bell’s palsy?

Various viruses may trigger Bell’s palsy. The condition occurs when swelling or inflammation temporarily puts pressure on the nerve that controls facial muscles. This pressure impairs the function of the nerve making it difficult for you to control facial muscles or expressions. As the inflammation subsides, the nerve starts to function again. It may take several months for symptoms to go away.

What are the symptoms of Bell’s palsy?

Symptoms of Bell’s palsy tend to come on suddenly and reach peak severity within 48 to 72 hours. Some people develop mild symptoms. Others experience total paralysis.

Symptoms start to gradually improve in three weeks. Up to 80% of people fully recover and show no signs of Bell’s palsy within three months.

In addition to facial drooping, signs of Bell’s palsy include:

• Difficulty speaking, eating or drinking.
• Drooling.
• Dry eyes.
• Facial or ear pain.
• Headache.
• Loss of taste.
• Ringing in ears (tinnitus).
• Sensitivity to sounds.

How is Bell’s palsy diagnosed?

Your healthcare provider can make a diagnosis based on symptoms. Other conditions, including stroke, sarcoidosis and Lyme disease, can also cause facial paralysis. To rule out those causes, you may have one or more of these tests:

• Blood tests to check for conditions like Lyme disease or sarcoidosis.
• Electromyography (EMG) to measure nerve activity and damage. This test may help your provider predict how quickly you’ll recover.
• Magnetic resonance imaging (MRI) or computed tomography (CT) scans to rule out stroke or other causes of nerve damage.

How is Bell's palsy managed or treated?

Bell’s palsy improves without treatment. Still, your healthcare provider may recommend one or more of these therapies for symptom relief and a faster recovery:

• Oral corticosteroids, such as prednisone, decrease nerve swelling and may help you regain facial movement faster. This treatment is most effective when you start it within 48 hours of noticing symptoms.
• Antiviral medications, such as acyclovir for herpes, may speed recovery, although it's unclear how much benefit they provide. This treatment works best when combined with oral corticosteroids.
• Eye care is very important. Eyedrops, including artificial tears, soothe dry, irritated eyes. If your eyelid won’t close, you may need to wear an eye patch to protect the eye from irritants and injuries.
• Decompression surgery eases pressure on the nerve is rarely performed because it can cause hearing loss and permanent facial nerve damage.
• Functional facial plastic surgery procedures are options for people who don't recover to help correct facial asymmetry and assist with eyelid closure.

What are the complications of Bell’s palsy?

Eight out of 10 people with Bell’s palsy recover fully without any lingering problems. Unfortunately, 20% of people have long-term facial paralysis and drooping. While uncommon, Bell’s palsy can come back, usually within two years of the initial diagnosis. A recurrence may affect the same side of the face or the opposite side.

How does Bell’s palsy affect pregnancy?

For unknown reasons, pregnant women are three times more likely to develop Bell’s palsy than women who aren’t expecting. The condition typically occurs during the third trimester. You may be more likely to develop Bell’s palsy while pregnant if you have preeclampsia (high blood pressure) or gestational diabetes.

If your symptoms are severe, your healthcare provider may recommend treatment. Certain treatments, such as oral corticosteroids, may increase your risk of giving birth prematurely before the 37th week of pregnancy. Your healthcare provider can discuss treatment risks and benefits with you.

How can I prevent Bell’s palsy?

Currently, there isn’t any known way to prevent Bell’s palsy.

What is the prognosis (outlook) for people who have Bell’s palsy?

The majority of people who develop Bell’s palsy recover without treatment. You should notice a gradual lessening of symptoms within a few weeks. Depending on the extent of nerve damage, full recovery can take two to six months. Some symptoms last longer, and some people never fully recover.

When should I call the doctor?

If you experience new Bell’s palsy symptoms, such as facial drooping or paralysis of your face, contact your healthcare provider immediately. Your provider may want to rule out other causes, such as stroke. Starting treatment early may help speed up and improve your chance for recovery. You should also call your healthcare provider if you experience:

• Symptoms that don’t improve within three months.
• Chronic eye irritation.
• An eyelid that won’t close.
• Dehydration due to difficulty drinking and swallowing.
• Hearing loss.

What questions should I ask my doctor?

If you have Bell’s palsy, you may want to ask your healthcare provider:

• Why did I get Bell’s palsy?
• What is the best treatment for Bell’s palsy?
• Are there any treatment side effects?
• When will these symptoms go away?
• Can I get Bell’s palsy again?
• Can therapies like physical therapy or massage therapy speed recovery?
• Should I look out for signs of complications?

Physiotherapy Interventions

For physiotherapy interventions please see Facial Palsy page.
It is also important to provide information on care of the eye in order to prevent formation of corneal ulcer: see advice page on Dry Eye. Referral to an opthalmologist should be considered.
A number of people with Bell's Palsy suffer from Xerostomia, or Dry Mouth. This occurs because two of the three main salivary glands receive their parasympathetic nerve supply from the facial nerve: the sublingual and glossopharyngeal glands. (The parotid gland is not innervated by the facial nerve, so is unaffected.) See the advice page on Dry Mouth.
Bell's Palsy patients with long term facial paralysis may also start to experience dental problems: see advice page on Dental Issues in Facial Palsy.