Bell’s Palsy: Symptoms, Causes, Risk Factors, Complications

Bell’s palsy is a condition that causes sudden weakness in the muscles on one side of the face, resulting in drooping or weakness. This condition has gained attention recently due to numerous celebrities sharing their experiences on social media.


  • Rapid onset of mild weakness to total paralysis on one side of your face — occurring within hours to days
  • Facial droop and difficulty making facial expressions, such as closing your eye or smiling
  • Drooling
  • Pain around the jaw or in or behind your ear on the affected side
  • Increased sensitivity to sound on the affected side
  • Headache
  • A loss of taste
  • Changes in the amount of tears and saliva you produce
  • In rare cases, Bell’s palsy can affect the nerves on both sides of your face.


  • The exact cause of Bell’s palsy is unknown. Experts think it’s caused by swelling and inflammation of the nerve that controls the muscles on one side of the face.
  • It could be caused by a reaction that occurs after a viral infection.
  • Viruses that have been linked to Bell’s palsy include viruses that cause cold sores and genital herpes (herpes simplex), chickenpox and shingles (herpes zoster), infectious mononucleosis (Epstein-Barr), cytomegalovirus infections, respiratory illnesses (adenovirus), German measles (rubella), mumps (mumps virus), flu (influenza B), and hand-foot-and-mouth disease (coxsackievirus).
  • The nerve that controls facial muscles passes through a narrow corridor of bone on its way to the face. In Bell’s palsy, that nerve becomes inflamed and swollen — usually related to a viral infection.

Risk Factors:

  • Bell’s palsy occurs more often in people who are pregnant, especially during the third trimester, or who are in the first week after giving birth.
  • Have an upper respiratory infection, such as the flu or a cold
  • Have diabetes
  • Have high blood pressure
  • Have obesity
  • Recurrent attacks of Bell’s palsy are rare. But when they do recur, there’s often a family history of recurrent attacks. This suggests that Bell’s palsy might have something to do with your genes.


  • A mild case of Bell’s palsy typically disappears within a month.
  • Recovery from a more severe case where the face was completely paralyzed can vary.
  • Irreversible damage to your facial nerve.
  • Irregular regrowth of nerve fibers. This may result in involuntary contraction of certain muscles when you’re trying to move other muscles (synkinesis). For example, when you smile, the eye on the affected side may close.
  • Partial or complete blindness of the eye that won’t close. This is caused by excessive dryness and scratching of the clear protective covering of the eye (cornea).