Health Library

Bell's Palsy

Bell's Palsy

What is Bell's palsy?

Bell's palsy is an unexplained episode of facial muscle weakness or paralysis that begins suddenly and worsens over 48 hours. This condition results from damage to the facial nerve (the 7th cranial nerve), and pain and discomfort usually occurs on one side of the face or head.

Bell’s palsy can strike anyone at any age, but it occurs most often in pregnant women, and people who have diabetes, influenza, a cold, or another upper respiratory ailment. Bell's palsy affects men and woman equally. It is less common before age 15 or after age 60.

Bell's palsy is not considered permanent, but in rare cases it does not disappear. Currently, there is no known cure for Bell's palsy; however, recovery usually begins 2 weeks to 6 months from the onset of the symptoms. Most people with Bell's palsy recover full facial strength and expression.

What causes Bell's palsy?

The cause of Bell's palsy is not known. It has been suggested that the disorder is due to inflammation that is directed by the body's immune system against the nerve controlling movement of the face. The weakness or symptoms seen in Bell's palsy is sometimes associated with the following:

  • Diabetes
  • High blood pressure
  • Injury
  • Toxins
  • Lyme disease
  • Guillain-Barré syndrome
  • Sarcoidosis
  • Myasthenia gravis
  • Infection, especially following a viral infection with Herpes simplex virus (a virus that is related to the cause of the common "cold sores" of the mouth)

These conditions cause weakness through a different mechanism than the usual inflammation of Bell's palsy.

What are the symptoms of Bell's palsy?

The following are the most common symptoms of Bell's palsy. However, each person may experience symptoms differently. Symptoms may include:

  • Disordered movement of the muscles that control facial expressions, such as smiling, squinting, blinking, or closing the eyelid
  • Loss of feeling in the face
  • Headache
  • Tearing
  • Drooling
  • Loss of the sense of taste on the front two-thirds of the tongue
  • Hypersensitivity to sound in the affected ear
  • Inability to close the eye on the affected side of the face

The symptoms of Bell's palsy may resemble other conditions or medical problems. Always consult your health care provider for a diagnosis.

How is Bell's palsy diagnosed?

Your health care provider can usually diagnose Bell’s palsy by looking at your symptoms. There are no specific tests used to diagnose Bell’s palsy. However, your health care provider may order tests to rule out other conditions that can cause similar symptoms and to determine the extent of nerve involvement or damage. These tests may include:

  • Electromyography (EMG) to determine the extent of the nerve involvement
  • Blood tests to determine if another condition such as diabetes or Lyme disease is present
  • Magnetic resonance imaging (MRI) or computed tomography (CT) to determine if there is a structural cause for your symptoms.


It is important that your health care provider rule out the presence of a stroke or tumor that may cause symptoms similar to Bell’s palsy.

How is Bell's palsy treated?

If a specific cause for Bell’s palsy is identified, such as infection, that cause will be treated. Otherwise, the symptoms are treated as needed.

One uniformly recommended treatment for Bell's palsy is protecting the eye from drying at nighttime or while working at a computer. Eye care may include eye drops during the day, ointment at bedtime, or a moisture chamber at night. This helps to protect the cornea from being scratched, which is crucial to the management of Bell's palsy.

Your health care provider will prescribe other treatment for your condition based on the severity of your symptoms and your health history. Other treatment options include:

  • Steroid medications to reduce inflammation
  • Antiviral medications, such as acyclovir
  • Analgesics or moist heat to relieve pain
  • Physical therapy to stimulate the facial nerve

Some people may choose to use alternative therapies in the treatment of Bell's palsy, but there is no proof these alternative therapies actually make an absolute difference in a person's recovery. Such treatment may include:

  • Relaxation
  • Acupuncture
  • Electrical stimulation
  • Biofeedback training
  • Vitamin therapy, including B12, B6, and the mineral zinc

What are the complications of Bell's palsy?

Bell’s palsy usually resolves in time and causes no long-term complications. However, during the illness most people with Bell’s palsy are unable to close their eye on the affected side of their face. It is, therefore, important to protect the eye from drying at nighttime or while working at a computer. Eye care may include eye drops during the day, ointment at bedtime, or a moisture chamber at night. This helps to protect the cornea from being scratched.

Living with Bell's palsy

Bell’s palsy usually resolves in time and causes no long-term complications. It is important, however, to take medications as directed. It is also crucial that you protect the affected eye from drying. Use of eye drops during the day and ointment at bedtime can protect the cornea from scratching.

When should I call my health care provider?

Bell’s palsy usually starts to improve in 2 weeks but may take 3 to 6 months to return to normal. If there is no improvement or if any symptoms worsen, it is important to notify your health care provider.

Key points

  • Bell's palsy is an unexplained episode of facial muscle weakness or paralysis that usually resolves on its own and causes no complications.
  • The cause of Bell’s palsy is unknown but is thought to be caused by inflammation affecting the body’s immune system. It is associated with other conditions such as diabetes.
  • Symptoms of facial weakness or paralysis get worse over the first few days and start to improve in about 2 weeks.
  • It can take 3 to 6 months to resolve completely.
  • Medications and eye care are important in treating Bell’s palsy.

Next steps

Tips to help you get the most from a visit to your health care provider:

  • Before your visit, write down questions you want answered.
  • Bring someone with you to help you ask questions and remember what your provider tells you.
  • At the visit, write down the names of new medicines, treatments, or tests, and any new instructions your provider gives you.
  • If you have a follow-up appointment, write down the date, time, and purpose for that visit.
  • Know how you can contact your provider if you have questions.
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