Definition:
Bell's palsy occurs when the nerve that controls facial muscles on one side of your face becomes swollen or inflamed. As a result of Bell's palsy, your face feels stiff. Half your face appears to droop, your smile is one-sided, and your eye resists closing.
Bell's palsy can affect anyone, but rarely affects people under the age of 15 or over the age of 60.
For most people, Bell's palsy symptoms improve within a few weeks, with complete recovery in three to six months. About 10 percent will experience a recurrence of Bell's palsy, sometimes on the other side of the face. A small number of people continue to have some Bell's palsy signs and symptoms for life.
Causes:
The most common cause of Bell's palsy appears to be the herpes simplex virus, which also causes cold sores and genital herpes. Other viruses that have been linked to Bell's palsy include:
The virus that causes chickenpox and shingles (herpes zoster)
The virus that causes mononucleosis (Epstein-Barr)
Another virus in the same family (cytomegalovirus)
With Bell's palsy, the nerve that controls your facial muscles, which passes through a narrow corridor of bone on its way to your face, becomes inflamed and swollen — usually from a viral infection. Besides facial muscles, the nerve affects tears, saliva, taste and a small bone in the middle of your ear.
Risk factors:
Bell's palsy occurs more often in people who:
Are pregnant, especially during the third trimester, or who are in the first week after giving birth
Have diabetes
Have an upper respiratory infection, such as the flu or a cold
Also, some people who have recurrent attacks of Bell's palsy, which is rare, have a family history of recurrent attacks. In those cases, there may be a genetic predisposition to Bell's palsy
Treatments and drugs
Most people with Bell's palsy recover fully — with or without treatment. But your doctor may suggest medications or physical therapy to help speed your recovery. Surgery is rarely an option for Bell's palsy.
Medications
Study results have been mixed regarding the effectiveness of two types of drugs commonly used to treat Bell's palsy: corticosteroids and antiviral drugs.
Corticosteroids, such as prednisone, are powerful anti-inflammatory agents. If they can reduce the swelling of the facial nerve, it will fit more comfortably within the bony corridor that surrounds it.
Antiviral drugs, such as acyclovir or valacyclovir, may stop the progression of the infection if a virus is known to have caused it.
Some clinical studies show benefit from early treatment with corticosteroids, antivirals or a combination of both types of drugs. Other studies don't. Evidence of the effectiveness of corticosteroids appears to be stronger than that for antiviral drugs, and they tend to be most effective when given within three days of the appearance of symptoms.
Physical therapy
Paralyzed muscles can shrink and shorten, causing permanent contractures. A physical therapist can teach you how to massage and exercise your facial muscles to help prevent this from occurring.
Surgery
One way to relieve the pressure on the facial nerve is to surgically open the bony passage through which it passes. This decompression surgery is controversial and rarely recommended. In some cases, however, plastic surgery may be needed to make your face look and work better.