Bell's Palsy: What Causes Bell's Palsy & Best Treatment for Full Recovery
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This article will review the symptoms, causes, diagnosis, and treatment of the condition Bell’s palsy. The main symptom of this condition is paralysis of facial muscles.
What is Bell's palsy?
Bell’s palsy can present as acute or chronic facial paralysis. This paralysis is usually sudden in onset and worsens over the course of 48 hours. Resolution of symptoms usually occurs within two weeks to six months but permanent paralysis can rarely occur. Symptoms of this condition are a result of the paralysis of facial muscles. This paralysis usually occurs only on one side of the face. The cause of Bell’s palsy is inflammation or damage to the facial nerve, also known as cranial nerve VII. This nerve controls the muscles of the face. Treatment is aimed at reducing inflammation or targeting the underlying cause of facial nerve paralysis.
You should visit your primary care physician to confirm the diagnosis and discuss treatment options. However, some cases do not require treatment as symptoms go away on their own.
Bell's palsy symptoms
This section will provide an overview of the symptoms associated with Bell’s palsy. Many of these symptoms are due to paralysis of the nerve and subsequent weakness of the facial muscles:
- Impaired ability to smile, squint, blink
- Inability to close the eyelid on the affected side
- Loss of facial sensation
- Loss of taste on the anterior portion of the tongue
- Dry eye or dry mouth
- Facial twitching
- Impaired hearing on the affected side
There are no specific tests used for the diagnosis of Bell’s palsy so it must be decided on the basis of clinical presentation. Some tests may be used to rule out other conditions that can cause facial paralysis. These tests help determine if you have diabetes or Lyme disease, both of which can present with similar symptoms. Other diagnostic workup may include MRI imaging if a provider is worried that a tumor along the facial nerve or a stroke might be causing the paralysis. Electromyography (EMG) can be used to determine how extensively the nerve is affected.
Bell's palsy causes
Bell’s palsy is considered a diagnosis of exclusion. That is, other possible causes of facial paralysis must be ruled out before the diagnosis of Bell’s palsy can be made. The paralysis of the facial nerve is due to the inflammation surrounding the nerve. Researchers of Bell’s palsy have noted that nerve biopsies of Bell’s palsy patients have a proliferation of inflammatory cells and compromise of myelin, the encasing of the nerve that allows conductive signals to move.
Treatment options and prevention for Bell's palsy
The management of Bell’s palsy is centered around reducing symptoms and decreasing inflammation. You will likely receive oral steroids to reduce inflammation. People with herpes simplex virus will receive the antiviral medication acyclovir. This condition can oftentimes be painful so you will also likely receive analgesic medications. There is strong evidence that oral steroids improve the chance of full recovery . Everyone with Bell’s palsy is also given instructions for eye care during the course of the disease. As your ability to close your eye may be compromised during Bell’s palsy, lubricants will be prescribed to prevent the eye from drying out.
Bell’s palsy is an idiopathic condition meaning that the cause is often unknown. Other causes of facial paralysis, such as diabetes, are more preventable by ensuring good control of blood sugar levels. Lyme disease, another cause of facial paralysis, can be prevented with protective clothing in wooded areas and thorough examination after exposure to at-risk areas.
When to seek further consultation for Bell's palsy
If you are experiencing new onset facial paralysis, you should consult your physician immediately for further management.
Questions your doctor may ask to determine Bell's palsy
- What is your race?
- Do you currently smoke?
- What is your body mass?
- Have you ever been diagnosed with diabetes?
- Are you having any difficulty walking?
Self-diagnose with our free Buoy Assistant if you answer yes on any of these questions.
Dr. Henry is a first-year resident in the Department of Otolaryngology-Head & Neck Surgery at the University of Pennsylvania. She received her medical degree from the University of Pennsylvania and her BA in political economy from Williams College. As a medical student, she was the editorial manager of an otolaryngology publication and has extensive experience with medical writing. She is currently working on research projects for publication in the sub-specialty fields of otology, head and neck cancer, and facial plastics. Outside the hospital she enjoys fly fishing, squash, hiking, and watching pro tennis.
- Bell’s Palsy. Johns Hopkins Health Library. Johns Hopkins Link
- Bell’s Palsy. U.S. National Library of Medicine: Medline Plus. Updated on Dec. 6, 2017. MedlinePlus Link
- Bell’s Palsy: Treatment with Steroids and Antiviral Drugs. American Academy of Neurology. AAN Link
- Liston SL, Kleid MS. Histopathology of Bell's palsy. Laryngoscope. 1989;99(1):23-6. PubMed Link