Authored by MCN Neurologists
Bell’s palsy is one-sided facial weakness/paralysis of the muscles around the eye and the mouth innervated by cranial nerve seven.
Symptoms of Bell’s Palsy
Most often patients first notice some pain behind the ear. This is followed by weakness of the facial muscles on the same side. Patients may find themselves not able to smile or close their eyes. Excessive tearing, sound sensitivity and a feeling of facial numbness can also accompany the weakness.
Causes of Bell’s Palsy
The exact cause of Bell’s palsy is not known. Many people believe it is associated with a viral infection resulting in inflammation of the seventh cranial nerve. Sixty percent of patients have some sort of viral illness prior to developing symptoms of Bell’s palsy. The virus that is most often suspected as causing Bell’s palsy is the herpes simplex type 1 (also associated with cold sores). Other viruses may be involved. Being diabetic or pregnant also increases the risk of developing Bell’s palsy. Lyme disease can also cause the same nerve injury and can be bilateral.
Bell’s Palsy Examination and Tests
When you visit the doctor, expect to undergo a thorough history and neurological examination. If only the lower half of your face is weak, or if there are other unusual findings on your exam suggesting more than a Bell’s palsy, you may be sent for imaging studies of your head. Some blood tests may also be done looking for other causes of facial weakness.
Treatment of Bell’s Palsy
Treatment for Bell’s palsy has been a controversial topic, mainly because the exact cause of the illness is not known. If you present with symptoms for less than 72 hours, expect to be given a prescription for prednisone. Some physicians will also prescribe acyclovir or valacyclovir, antiviral medications. The purpose of the treatment is to improve the weakness in the face. After 72 hours of symptoms, most physicians will not prescribe any medications. Eighty percent of patients fully recover from the illness. Of the 20% of patients left with some facial weakness, only 5% have severe residual effects.
All patients will need to use eye ointments placed in the eye at night. The weakness causes patients to be unable to close their eye, even while sleeping. Without ointment, patients are at high risk of developing corneal abrasions. Use of natural tears can help with any dry eye symptoms during the day.
For further information about Bell’s palsy, click on the following link:
www.ninds.nih.gov/disorders/bells/detail_bells.htm (National Institute of Neurological Diseases and Stroke)
January 1, 2010
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