facial nerve palsy is the diminished function of the facial nerve or one of its branches. Bell’s palsy, which results in the complete inability to move one side of the face, is the most common cause of facial nerve palsy. This condition completely or completely improves within a few months, and it doesn’t cause harm to overall health.
There are other types and causes of facial nerve palsy, and they tend to be longer-lasting and more concerning than Bell’s palsy. This article will discuss the symptoms, causes, diagnosis, and treatment of facial nerve palsy.
Facial Nerve Palsy Symptoms
Facial nerve palsy affects one side of the face. It can affect the whole side or just part of a side of the face. The main symptom is weakness, but sometimes sensory changes, like tingling or loss of sensation, can also occur.
Symptoms of facial nerve palsy include:
- Droopy eyelid
- Eyelid that won’t close
- Dropy cheek
- Flattening of the nasolabial fold (the crease above the smile)
- Lopsided smile
- Uneven face
These symptoms can affect the forehead, the lower part of the face, or the upper and lower part of the face. Facial nerve palsy affects only one side of the face.
Associated symptoms can include tingling, numbness, burning, pain, diminished sensation, hearing loss, or dizziness. Facial nerve palsy can cause complications due to the inability to move parts of the face. Complications are more likely if the condition lasts for a long time and if the weakness is severe.
Problems that can occur due to facial palsy include:
- dry eye
- Corneal damage (damage to the clear dome of tissue at the front of the eye)
- Infection of the eye
- Vision problems due to a droopy eyelid
- Difficulty chewing
- Trouble swallowing
- Choking on food, drinks, or saliva
- Trouble breathing
These complications can be serious, but they can often be prevented with measures such as wearing an eye patch to protect the eye.
Facial nerve palsy can be caused by inflammation or damage to the facial nerve. The most common condition that causes facial nerve palsy is Bell’s palsy. It is considered idiopathic (without a known specific cause or trigger) and is believed to result from inflammation.
Other causes can include trauma or an injury to the facial nerve or one of its branches. This may occur due to an accident or as a result of a procedure, such as the removal of a tumor that has grown near the facial nerve.
Ramsay Hunt syndrome is a condition involving facial nerve weakness that can occur as a complication of shingles (a painful rash that can occur years after recovering from a chicken pox infection).
Neuropathy (nerve disease), inflammatory diseases (such as lupus), an infection, or cancer invading the nerve may cause facial nerve palsy as well—although these causes are not common.
Facial nerve palsy is diagnosed based on a history of symptoms and a physical examination. Weakness of the face caused by a facial nerve problem can affect the forehead, whereas weakness of the face caused by a problem in the brain—like a stroke—will not typically affect the forehead.
A careful neurological examination can help determine whether facial weakness is caused by a condition affecting the nerve or by a condition affecting the brain.
An examination of the mouth, throat, and face can determine if there is swelling or evidence of an infection. Examination of eye movements and vision can help identify whether other cranial nerves besides the facial nerve are involved.
Sometimes tests may be needed to help identify the cause of facial nerve palsy.
These can include:
- Blood tests may identify features of an infection or inflammation.
- Brain imaging studies may identify other potential causes of facial weakness, such as a brain aneurysm (bulge in an artery in the brain) or multiple sclerosis (a condition in which the immune system mistakenly attacks the protective lining of the nerves).
- Electromyography (EMG) or nerve conduction studies (NCV) can examine the function of the muscles and nerves, which may help identify unusual patterns of nerve damage.
- Rarely, a spinal tap (also called a lumbar puncture) is done to look for signs of infection, inflammation, or cancer in the spinal fluid.
When to See a Healthcare Provider
Get medical attention if you develop new facial weakness, numbness, swelling, pain, trouble speaking, or difficulty chewing or swallowing.
Sometimes medical or surgical interventions can help alleviate some of the effects and symptoms of facial nerve palsy. Generally, Bell’s palsy improves without treatment, but often, treatment with oral steroids can speed up recovery and reduce long-term effects.
If facial nerve palsy occurs in an association with an inflammatory disorder, anti-inflammatory medication may be prescribed. And for treatment of a bacterial infection, antibiotics and drainage of an abscess (walled-off pocket of infection and pus) may be necessary.
Surgery may benefit some people who have facial nerve palsy. Procedures can include nerve transfer, muscle transfer, or repair of the nerve. Chemotherapy is an option for people who have facial nerve palsy due to cancer.
For anyone who has facial nerve palsy of any cause, lifestyle modifications and rehabilitation can help with movement and with preventing complications. This can include speech and swallow therapy, as well as facial exercises.
Facial nerve palsy is damage or disease of the facial nerve. It causes weakness of movement on one side of the face. Bell’s palsy, a nerve injury, and Ramsay Hunt syndrome are the most common causes. Other less common causes include an infection, inflammation, cancer, and neuropathy.
Differentiating facial nerve palsy from brain disease, such as stroke or multiple sclerosis, is important because the urgency and treatment differ based on the cause of facial weakness.
The treatment of facial nerve palsy often involves anti-inflammatory medication and physical therapy. Other treatments, such as antibiotics, chemotherapy, or surgery, are specific to the cause.
A Word From Verywell
Coping with facial weakness can be stressful. Seek medical attention if you develop this symptom. Facial nerve palsy will usually resolve, but it’s important to maintain strategies to avoid complications—such as preventive eye damage from being unable to close the eyelid.
After you recover from an episode of facial nerve palsy, you can continue to do your muscle exercises until you feel that you have regained adequate control of your facial movements.
Frequently Asked Questions
What is the most common cause of facial nerve palsy?
Bell’s palsy is the most common cause of facial nerve palsy. It is often considered idiopathic (without an identifiable cause), and it is sometimes preceded by an infection or inflammation. This condition is not dangerous.
Generally, Bell’s palsy causes severe facial weakness on one side of the face, including the forehead, and it resolves on its own.
How long does facial nerve palsy typically last?
It depends on the cause. Bell’s palsy can last between a few weeks and a few months, sometimes with mild facial weakness persisting for a year or longer. Other causes of facial nerve palsy—like nerve damage—may be permanent until they are treated.
Can stress cause facial paralysis?
Stress does not cause facial paralysis, but it is associated with Bell’s palsy. The condition can cause stress, and stress may worsen the condition and prolong symptoms.