Bell's palsy is a form of temporary facial paralysis resulting from damage or trauma to one of the facial nerves. It is the most common cause of facial paralysis. Generally, Bell's palsy affects only one of the paired facial nerves and one side of the face, however, in rare cases, it can affect both sides. Symptoms of Bell's palsy usually begin suddenly and reach their peak within 48 hours. Symptoms vary from person to person and can range in severity from mild weakness to total paralysis. These symptoms include twitching, weakness, or paralysis, drooping eyelid or corner of the mouth, drooling, dry eye or mouth, impairment of taste, and excessive tearing in the eye. Bell’s palsy often causes significant facial distortion. Most scientists believe that a viral infection such as viral meningitis or the common cold sore virus -- herpes simplex-- can cause the disorder when the facial nerve swells and becomes inflamed in reaction to the infection.
Recent studies have shown that steroids such as prednisone -- used to reduce inflammation and swelling -- are an effective
treatment for Bell's palsy. Other drugs such as acyclovir -- used to fight viral herpes infections -- may also have some benefit in shortening the course of the disease. Analgesics
such as aspirin, acetaminophen, or ibuprofen may relieve pain. Because of possible drug interactions, individuals should
always talk to their doctors before taking any over-the-counter medicines. Keeping the eye moist and protecting it from debris and injury, especially at night, is important. Physical therapy to
stimulate the facial nerve and help maintain muscle tone may benefit some individuals.
The prognosis for individuals with Bell's palsy is generally very good. The extent of nerve damage determines the extent of
recovery. With or without treatment, most individuals begin to get better within 2 weeks after the initial onset of symptoms and recover
completely within 3 to 6 months.
The National Institute of Neurological Disorders and Stroke (NINDS) conducts and supports an extensive research program of
basic science to increase understanding of how the nervous system works and what causes the system to sometimes go awry, leading
to dysfunction. Part of this research program focuses on learning more about the circumstances that lead to nerve damage and
the conditions that cause injuries and damage to nerves. Knowledge gained from this research may help scientists find the
definitive cause of Bell's palsy, leading to the discovery of new effective treatments for the disorder. Other NINDS-supported
research is aimed at developing methods to repair damaged nerves and restore full use and strength to injured areas, and finding
ways to prevent nerve damage and injuries from occurring.
National Organization for Rare Disorders (NORD) 55 Kenosia Avenue Danbury, CT 06810 orphan@rarediseases.org http://www.rarediseases.org Tel: 203-744-0100 Voice Mail 800-999-NORD (6673) Fax: 203-798-2291 |
Prepared by:
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National Institute of Neurological Disorders and Stroke
National Institutes of Health
Bethesda, MD 20892
NINDS health-related material is provided for information purposes only and does not necessarily represent endorsement by or an official position of the National Institute of Neurological Disorders and Stroke or any other Federal agency. Advice on the treatment or care of an individual patient should be obtained through consultation with a physician who has examined that patient or is familiar with that patient's medical history.
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Last updated September 4, 2012