Bell's palsy

Because the facial nerve has so many functions and is so complex, damage to the nerve or a disruption in its function can lead to many problems. Symptoms of Bell's palsy, which vary from person to person and range in severity from mild weakness to total paralysis, may include twitching, weakness, or paralysis on one or both sides of the face, drooping of the eyelid and corner of the mouth, drooling, dryness of the eye or mouth, impairment of taste, and excessive tearing in one eye. Most often these symptoms, which usually begin suddenly and reach their peak within 48 hours, lead to significant facial distortion.^[3]

Other symptoms may include pain or discomfort around the jaw and behind the ear, ringing in one or both ears, headache, loss of taste, hypersensitivity to sound on the affected side, impaired speech, dizziness, and difficulty eating or drinking.^[3]

Bell's palsy occurs when the nerve that controls the facial muscles, the 7th cranial nerve, is swollen, inflamed, or compressed, resulting in facial weakness or paralysis. Exactly what causes this damage is unknown.^[1][3]

Many scientists believe that a viral infection such as viral meningitis or the common cold sore virus -- herpes simplex-- causes the disorder when the facial nerve swells and becomes inflamed in reaction to the infection.^[2] The disorder has also been associated with influenza or a flu-like illness, headaches, chronic middle ear infection, high blood pressure, diabetes, sarcoidosis, tumors, Lyme disease, and trauma such as skull fracture or facial injury.^[3] There may also be an inherited tendency toward developing Bell's palsy.^[1]

Some cases of Bell's palsy are mild and do not require treatment.^[1][3] In these cases, symptoms may subside on their own within 2 weeks.^[3] For those cases that do require treatment, steroids such as prednisone have been used with success to reduce inflammation and swelling.  Other medications such as acyclovir --used to fight viral infections -- may shorten the course of the disease.  Analgesics such as aspirin, acetaminophen, or ibuprofen may relieve pain. Because of possible drug interactions, patients should always talk to their doctors before taking any over-the-counter medicines. Keeping the eye moist and protected from debris and injury is important. Other therapies such as physical therapy, facial massage or acupuncture may also be used.^[2][3] In general, decompression surgery for Bell's palsy is controversial and is seldom recommended.^[3]

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.^[2][3] For some, however, the symptoms may last longer. In a few cases, the symptoms may never completely disappear. In rare cases, the disorder may recur, either on the same or the opposite side of the face.^[3]