Bell's palsy is an unexplained episode of facial muscle weakness or paralysis that begins suddenly and worsens over 48 hours. It is caused by a damaged facial nerve.
What is Bell's palsy?
Bell's palsy is an unexplained episode of facial muscle weakness or paralysis. It begins suddenly and can worsen over 48 hours. This condition results from damage to the facial nerve (the 7th cranial nerve). Pain and discomfort usually occur on one side of the face or head.
Bell’s palsy can strike anyone at any age. It occurs most often in pregnant women, and people who have diabetes, influenza, a cold, or another upper respiratory ailment. Bell's palsy affects men and woman equally. It is less common before age 15 or after age 60.
Bell's palsy is not considered permanent. But in rare cases, it does not disappear. Currently, there is no known cure for Bell's palsy. Recovery, though, usually begins 2 weeks to 6 months from the onset of the symptoms. Most people with Bell's palsy recover full facial strength and expression.
What causes Bell's palsy?
The cause of Bell's palsy is not known. It is thought that it may be due to inflammation that is directed by the body's immune system against the nerve controlling movement of the face. Bell's palsy is sometimes associated with the following:
High blood pressure
Infection, especially following a viral infection with Herpes simplex virus. This is a virus that is related to the cause of the common "cold sores" of the mouth.
What are the symptoms of Bell's palsy?
These are the most common symptoms of Bell's palsy:
Disordered movement of the muscles that control facial expressions, such as smiling, squinting, blinking, or closing the eyelid
Loss of the sense of taste on the front 2/3 of the tongue
Hypersensitivity to sound in the affected ear (hyperacusis)
Inability to close the eye on the affected side of the face
The symptoms of Bell's palsy may look like other health problems, such as Guillain-Barre syndrome, myasthenia, and multiple sclerosis. Always see your healthcare provider for a diagnosis.
How is Bell's palsy diagnosed?
Your healthcare provider can usually diagnose Bell’s palsy by looking at your symptoms. There are no specific tests used to diagnose Bell’s palsy. But your healthcare provider may order tests to rule out other conditions that can cause similar symptoms and to determine the extent of nerve involvement or damage. These tests may include:
Electromyography (EMG) to determine the extent of the nerve involvement
Blood tests to determine if another condition such as diabetes or Lyme disease is present
MRI or CT scan to find out if there is a structural cause for your symptoms
How is Bell's palsy treated?
If a specific cause for Bell’s palsy is identified, such as infection, that cause will be treated. Otherwise, the symptoms are treated as needed.
One uniformly recommended treatment for Bell's palsy is protecting the eye from drying at night or while working at a computer. Eye care may include eye drops during the day, ointment at bedtime, or a moisture chamber at night. This helps protect the cornea from being scratched, which is crucial to the management of Bell's palsy.
Your healthcare provider will prescribe other treatment for your condition based on the severity of your symptoms and your health history. Other treatment options include:
Steroids to reduce inflammation
Antiviral medicine, such as acyclovir
Analgesics or moist heat to relieve pain
Physical therapy to stimulate the facial nerve
Some people may choose to use alternative therapies in the treatment of Bell's palsy, but there is no proof they make a difference in recovery. Such treatment may include:
Vitamin therapy, including B12, B6, and the mineral zinc
What are possible complications of Bell's palsy?
Bell’s palsy usually resolves in time and causes no long-term complications. But during the illness, most people with Bell’s palsy are unable to close their eye on the affected side of their face. It is, therefore, important to protect the eye from drying at night or while working at a computer. Eye care may include eye drops during the day, ointment at bedtime, or a moisture chamber at night. This helps protect the cornea from being scratched.
Living with Bell's palsy
Bell’s palsy usually resolves in time and causes no long-term complications. It is important, though, to take medicines as directed. It is also crucial that you protect the affected eye from drying. Use of eye drops during the day and ointment at bedtime can protect the cornea from scratching.
When should I call my healthcare provider?
Bell’s palsy usually starts to improve in 2 weeks but may take 3 to 6 months to return to normal. If there is no improvement or if any symptoms worsen, it is important to tell your healthcare provider.
Key points about Bell's palsy
Bell's palsy is an unexplained episode of facial muscle weakness or paralysis that usually resolves on its own and causes no complications.
The cause of Bell’s palsy is unknown. But it is thought to be caused by inflammation affecting the body’s immune system. It is associated with other conditions such as diabetes.
Symptoms of facial weakness or paralysis get worse over the first few days and start to improve in about 2 weeks.
It can take 3 to 6 months to fully resolve.
Medicine and eye care are important in treating Bell’s palsy.
Tips to help you get the most from a visit to your healthcare provider:
Know the reason for your visit and what you want to happen.
Before your visit, write down questions you want answered.
Bring someone with you to help you ask questions and remember what your provider tells you.
At the visit, write down the name of a new diagnosis, and any new medicines, treatments, or tests. Also write down any new instructions your provider gives you.
Know why a new medicine or treatment is prescribed, and how it will help you. Also know what the side effects are.
Ask if your condition can be treated in other ways.
Know why a test or procedure is recommended and what the results could mean.
Know what to expect if you do not take the medicine or have the test or procedure.
If you have a follow-up appointment, write down the date, time, and purpose for that visit.
Know how you can contact your provider if you have questions.
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