Bell's palsy causes sudden, temporary weakness in your facial muscles. This makes half of your face appear to droop. Your smile is one-sided, and your eye on that side resists closing.
Bell's palsy, also known as facial palsy, can occur at any age. The exact cause is unknown. It's believed to be the result of swelling and inflammation of the nerve that controls the muscles on one side of your face. Or it might be a reaction that occurs after a viral infection.
For most people, Bell's palsy is temporary. Symptoms usually start to improve within a few weeks, with complete recovery in about six months. A small number of people continue to have some Bell's palsy symptoms for life. Rarely, Bell's palsy can recur.
Signs and symptoms of Bell's palsy come on suddenly and may include:
In rare cases, Bell's palsy can affect the nerves on both sides of your face.
Seek immediate medical help if you experience any type of paralysis because you may be having a stroke. Bell's palsy is not caused by a stroke, but it can cause similar symptoms.
See your doctor if you experience facial weakness or drooping to determine the underlying cause and severity of the illness.
Although the exact reason Bell's palsy occurs isn't clear, it's often related to exposure to a viral infection. Viruses that have been linked to Bell's palsy include the virus that causes:
The nerve that controls your facial muscles passes through a narrow corridor of bone on its way to your face. In Bell's palsy, that nerve becomes inflamed and swollen â usually related to a viral infection. Besides facial muscles, the nerve affects tears, saliva, taste and a small bone in the middle of your ear.
There's no specific test for Bell's palsy. Your doctor will look at your face and ask you to move your facial muscles by closing your eyes, lifting your brow, showing your teeth and frowning, among other movements.
Other conditions â such as a stroke, infections, Lyme disease and tumors â can also cause facial muscle weakness, mimicking Bell's palsy. If the cause of your symptoms isn't clear, your doctor may recommend other tests, including:
A mild case of Bell's palsy normally disappears within a month. Recovery from a more severe case involving total paralysis varies. Complications may include:
Although there's little scientific evidence to support the use of alternative medicine for people with Bell's palsy, some people with the condition may benefit from the following:
Home treatment may include:
Bell's palsy occurs more often in people who:
Recurrent attacks of Bell's palsy are rare. But in some of these cases, there's a family history of recurrent attacks â suggesting a possible genetic predisposition to Bell's palsy.