Diseases & Conditions

Bell Palsy

Overview, Causes, & Risk Factors

Bell's palsy is a form of facial paralysis on one side of the face resulting from damage to the seventh cranial nerve.

What is going on in the body?

Bell's palsy is thought to be due to inflammation of the seventh cranial nerve. This nerve is called the facial nerve. Bell's palsy tends to come on very suddenly. Some people notice pain behind the ear a day or two before they notice any facial muscle weakness.

What are the causes and risks of the disease?

Bell's palsy is caused by a sudden breakdown of or damage to the nerve that supplies the muscles on one side of the face. Attacks often occur without a clear cause. The common cold sore virus, herpes simplex, is the likely cause of most cases of Bell's palsy. Bell's palsy is more common in pregnant women, people recovering from a viral infection, and people with diabetes.

Symptoms & Signs

What are the signs and symptoms of the disease?

Symptoms include:

  • decreased sense of taste
  • difficulty chewing on the affected side
  • drooling
  • dropping of the mouth at one corner
  • excess or decreased tearing
  • fear that a stroke has occurred
  • hypersensitivity to sound in the affected ear
  • inability to blink or close the eye on the affected side
  • pain in the face or ear
  • twitching of muscles on the affected side

  • Diagnosis & Tests

    How is the disease diagnosed?

    Other disorders, such as stroke and some tumors, can also cause similar symptoms. A doctor can determine if the problem is Bell's palsy based on the specific symptoms. The doctor may also use blood tests, an MRI, or a CAT scan.

    Prevention & Expectations

    What can be done to prevent the disease?

    Basic wellness methods may help prevent Bell's palsy. This is because the common cold sore virus is often involved. A healthy diet, adequate exercise, and stress management are all important.

    What are the long-term effects of the disease?

    The prognosis for Bell's palsy is good. With or without treatment, most people begin to feel better within 2 weeks. About 80% recover completely within 3 months. In a few people, symptoms may last longer or even fail to disappear completely. Bell's palsy affects only one side of the face at a time. It is possible, though not usual, for Bell's palsy to occur again in the same person. Experts do not agree on the rate of recurrence, but at most it is only 10 to 15%.

    What are the risks to others?

    Bell's palsy is not contagious. People who have it can return to work and their usual activities as soon as they feel ready.

    Treatment & Monitoring

    What are the treatments for the disease?

    It is important to consult a doctor right away once symptoms begin. Recent studies have shown that steroids are probably effective in treating this condition and relieving some of the symptoms. The antiviral drug, acyclovir, is possibly effective in improving facial function when used in combination with steroids. Painkillers may also help. Other treatments include:

  • patching the eye shut
  • performing surgery to restore partial nerve function
  • using eye drops to prevent the eye from drying out
  • In addition, rest is important in aiding healing from the facial nerve trauma. It is normal to feel more tired than usual during this period. Frequent brushing of the teeth and rinsing of the mouth can help get rid of food that gets stuck between the gum and cheek. An earplug can help prevent discomfort from noise sensitivity. Moist heat can provide some short-term relief from facial pain.

    What are the side effects of the treatments?

    Preventing eye problems with eye drops and an eye patch is very important. Sometimes eye drops and steroids can have side effects. Any side effects should be reported to the doctor.

    What happens after treatment for the disease?

    With or without treatment, most people begin to get significantly better in 2 weeks. About 80% recover completely in 3 months.

    How is the disease monitored?

    Checking in with a doctor during the period of facial paralysis is important to make sure there are no added complications. This condition can create anxiety because the palsy symptoms can look like a stroke. Any new or worsening symptoms should also be reported to the doctor.


    Author:Dr. Karen Wolfe, MBBS, MA
    Date Written:
    Editor:Crist, Gayle P., MS, BA
    Edit Date:06/16/02
    Reviewer:Kathleen A. MacNaughton, RN, BSN
    Date Reviewed:06/15/02


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