DefinitionBy Mayo Clinic staff
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.
Signs and symptoms of Bell's palsy come on suddenly, and may include:
- Rapid onset of mild weakness to total paralysis on one side of your face — occurring within hours to days — making it difficult to smile or close your eye on the affected side
- Facial droop and difficulty making facial expressions
- Pain around the jaw or in or behind your ear on the affected side
- Increased sensitivity to sound on the affected side
- A decrease in your ability to taste
- Changes in the amount of tears and saliva you produce
When to see a doctor
Seek immediate medical help if you experience paralysis, because you may be having a stroke. Actual Bell's palsy is not caused by a stroke.
See your doctor if you experience facial weakness or drooping, to determine the underlying cause and severity of the illness.
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)