Bell's Palsy
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Bell's Palsy

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Bell's palsy is a sudden weakness and paralysis on one side of the face. It occurs in approximately 40,000 Americans each year and affects men and women equally.

Bell's Palsy: Facial Droop

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The cause of Bell's palsy is unknown. It is suspected that an irritated facial nerve becomes swollen due to inflammation. As the facial nerve passes through narrow openings in the skull, it is compressed and symptoms result.

Doctors believe a herpes virus may cause the nerve to become inflamed, and, in turn, cause Bell’s palsy. Lyme disease may also be a cause.

Paralysis of the facial nerve may be caused by:

  • Head or facial injuries
  • Tumors
  • Strokes
  • Abscess
  • HIV
  • Infection
  • Autoimmune disease
  • Drug therapy such as chemotherapy
  • Hereditary diseases
  • Other medical problems may also cause paralysis of the facial.

Risk Factors

A risk factor is something that increases your chance of getting a disease or condition. Risk factors for Bell's palsy include:


Bell's palsy symptoms may come on suddenly or develop over a few days. Initial symptoms may include:

  • Pain behind the ear that precedes the weakness and paralysis
  • Ringing sound in the ears
  • Slight fever
  • Slight hearing impairment
  • Slight increase in sensitivity to sound on the affected side.

Symptoms of full-blown Bell's palsy may include:

  • Facial weakness or paralysis:
    • Usually on one side
    • Forehead is smooth
    • Not able to smile
  • Numbness just before the weakness starts
  • Drooping corner of the mouth
  • Drooling
  • Decreased tearing
  • Inability to close an eye, which can lead to:
    • The eye becoming red and dehydrated
    • Ulcers forming on the cornea
    • Infection
    • Possible loss of the eye
  • Dry eye
  • Impaired taste
  • Sound sensitivity in one ear
  • Earache
  • Slurred speech

Late complications (occurring 3-4 months after onset) can include:

  • Contracture of the facial muscles
  • Tearing from eye during eating


The doctor will ask about your symptoms and medical history, and perform a physical exam.

Other tests may include:

  • Hearing test—to see if nerve damage involves the hearing nerve, inner ear, or hearing mechanism
  • Balance test—to see if balance nerves are involved
  • Lumbar puncture—to rule out meningitis , autoimmune disorders, or metastasis from a tumor
  • Tear test—measures the eye's ability to produce tears
  • CT or MRI scan—to see if there is an infection, tumor, bone fracture , or other problem in the area of the facial nerve
  • Electrical test—to determine damage to the facial nerve
  • Blood tests—to check for diabetes, HIV infection , or Lyme disease


In most cases, symptoms go away within a few weeks without treatment. Many cases of Bell's palsy completely resolve after a few months.

Protecting the eye is important because people with Bell’s palsy may not be able to blink. If an underlying cause of the symptoms is known, it is treated. For some patients, however, symptoms may never go away.

Below are several ways to treat Bell's palsy:


Corticosteroids or nonsteroidal anti-inflammatory drugs (NSAIDs) reduce inflammation and pain

Recent research has shown that steroids, such as prednisolone, can significantly improve the chance of complete recovery from Bell's palsy. *


Some doctors try to surgically relieve pressure on the nerve by removing part of the bone. This is an unproven procedure that is considered controversial and is no longer commonly performed. If the eyelid will not close, other surgeries around the eye may be considered.


Patients may need to apply lubricant or put drops in the eye. The eye can be covered and taped closed at night. Do not place tape directly on the eyelid. An eye patch may be worn to keep the eye closed. This helps moisten and keep particles out of the eye. Massage of the weakened facial muscles may be beneficial.


Most patients who do not recover are distressed by their symptoms. They may need help dealing with the emotional issues associated with the condition.


There are no guidelines for preventing Bell's palsy because the cause is unknown and there are no tests to detect it before symptoms begin. If you think you are at risk for Bell's palsy, talk to your doctor about ways to reduce your risk factors.


American Academy of Otolaryngology—Head and Neck Surgery

Bell's Palsy Research Foundation


BC Health Guide

Health Canada


American Academy of Otolaryngology—Head and Neck Surgery website. Available at: . Accessed October 12, 2005.

Bell’s palsy. EBSCO Publishing Dynamed website. Available at: . Updated February 20, 2008. Accessed February 23, 2008.

Bell’s palsy fact sheet. National Institute of Neurological Disorders and Stroke website. Available at: . Accessed August 2003.

Bell’s palsy information page. National Institute of Neurological Disorders and Stroke website. Available at: . Accessed August 2003.

Dambro MR. Griffith's 5-Minute Clinical Consult . Philadelphia, PA: Lippincott Williams & Wilkins; 1999.

Kasper DL, Braunwald E, Fauci AS, et al. Harrison's Principles of Internal Medicine . 16th ed. New York, NY: The McGraw-Hill Companies; 2005.

National Institute of Dental and Craniofacial Research website. Available at: . Accessed October 12, 2005.

New concepts in Bell's Palsy improve treatment options. Am Fam Physician . 2005;72:169.

Primary Care Medicine . 4th ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2000.

Rakel RE, Bope ET. Conn's Current Therapy 2001, 53rd ed. Philadelphia, PA: WB Saunders Company; 2001.

Russell J. Bells palsy. In: Gilman S, ed. MedLink Neurology. San Diego, CA: MedLink Corporation.

Samuels MA, Feske SK. Office Practice of Neurology . Philadelphia, PA: Churchill Livingstone; 2003.

*Updated section on Treatment on 11/6/2007 according to the following study, as cited by DynaMed's Systematic Literature Surveillance DynaMed's Systematic Literature Surveillance : Sullivan FM, Swan IR, Donnan PT, Morrison JM, Smith BH, McKinstry B, et al. Early treatment with prednisolone or acyclovir in Bell's palsy. N Engl J Med . 2007;357:1598-1607.

Last reviewed February 2008 by J. Thomas Megerian, MD, PhD, FAAP

Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.

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