What Is Bell’s Palsy?

Bell’s palsy is a nerve problem that affects the muscles of your face. It causes weakness or partial paralysis of the muscles on one side of your face. With Bell’s palsy, your eyelid may not close properly and your smile may seem uneven.

Bell’s palsy usually affects adults only. It is more likely to happen to people who have diabetes, are pregnant, or have a family history of Bell’s palsy.

What causes Bell’s palsy?

Generally, it is not known what causes Bell’s palsy. However, doctors believe it may be due to one or more of these problems:

  • problems in your body’s immune system (how it fights disease)
  • reduced blood flow to a nerve that goes to your face (the 7th cranial nerve)
  • infection from a virus, causing swelling of the facial nerves