What Is Bell’s Palsy
Bell’s palsy is a condition that causes sudden weakness in the muscles on one side of the face. In most cases, the weakness is temporary and significantly improves over the following days and weeks.
The muscle weakness makes half of the face appear to droop. Smiles are one-sided, lopsided, or at a noticeable incline, and the eye on the affected side might resist closing.
Bell’s palsy has an alias and is commonly referred to as acute peripheral facial palsy of unknown cause. The condition can occur at any age. The exact cause is unknown. Experts currently theorise that it is caused by swelling and inflammation of the nerve controlling the muscles on one side of the face. Another theory is that it could be caused by a reaction that occurs after a viral infection involving the neck lymph nodes.
Symptoms usually start to improve and reverse within a few days or weeks, with a complete recovery in about six months. A small number of people continue to have some Bell’s palsy symptoms for life.
Bell’s palsy rarely occurs more than once and rarely occurs on both sides of the face. The reason only one side of the face is affected has yet to be discovered.
What Are The Symptoms Of Bell’s Palsy
Signs and symptoms of Bell’s palsy come on suddenly, even overnight, and may include:
- Facial weakness
- Rapid onset of mild weakness to total paralysis on one side of the face — occurring within hours to days.
- Facial droop and difficulty making facial expressions, such as closing your eye or smiling.
- Lopsided lips with one side noticeable higher than the other on an incline.
- Pain around the jaw or in or behind your ear on the affected side
- Increased sensitivity to sound on the affected side
- A loss of taste
- Changes in the production volume of tears and saliva
- In rare cases, Bell’s palsy can affect the nerves on both sides of the face.
What Are The Known Causes Or Correlating Factors
Although the exact reason Bell’s palsy occurs has not been established definitively, it is often correlated to a viral infection. Viruses that have been linked to Bell’s palsy cases 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)
- 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 in response to the related viral infection.
Besides facial muscles, the same nerve also affects tears, saliva, taste, smell, and a small bone in the middle of the ear. Those areas may display mild signs of having been affected by the condition and remain long after the initial external palsy has resolved.
Are There Any Risk Factors For Bell’s Palsy
Bell’s palsy noticeably occurs more often in people who:
- Have an upper respiratory infection, such as the flu or a cold
- Have diabetes
- Are pregnant, especially during the third trimester, or who are in the first week after giving birth
- Have high blood pressure
- Have obesity
Recurrent attacks of Bell’s palsy are rare. In the few cases they do recur, there is often a family history of recurrent attacks suggesting that Bell’s palsy might be a genetic factor and predisposition is based on inherited genetics.
What Are The Possible Complications From Bell’s Palsy
A mild case of Bell’s palsy can literally appear overnight. You go to bed normal and wake up with your lips at a noticeable angle and one side of your face lower than the other. This form typically disappears or corrects itself for the most part within a month without any intervention.
Recovery from a more severe case where one side of the face was completely paralysed can vary and is dependent on the individual. Complications from a severe episode may include:
- Irreversible damage to the facial nerve.
- Irregular regrowth of nerve fibres. This may result in the involuntary contraction of certain muscles when you are trying to move other muscles, called synkinesis.
- Partial or complete blindness of the eye that won’t close.
- Eye injuries and discomfort are caused by excessive dryness and scratching of the cornea.
- Biting of the inner cheek and tongue due to numbness and lack of muscle control.
Warning Signs Before Bell’s Palsy
The early symptoms of Bell’s palsy may include a slight fever, pain behind the ear and weakness on one side of the face. The symptoms may begin suddenly and progress rapidly over several hours and sometimes follow a period of stress or reduced immunity. One whole side of the face is affected.
What Are The Treatment Options
Most people with mild Bell’s palsy recover fully without any medical treatment or intervention.
Gentle massage can maintain the mobility of the facial muscles and prevent the loss of muscle function as the nerve recovers.
Treatment with oral corticosteroid drugs such as prednisone has shown to be more successful than surgical attempts to widen the facial canal.
Steroids must be given within the first 72 hours of the onset of facial palsy to have optimal benefit.
It is best to avoid exercise while the face is flaccid as this can cause overactivity of the face following recovery and worsen synkinesis.
The inability to make facial expressions is not just a cosmetic issue but can cause significant eye health problems if the eyelids cannot close fully. If the eye surface is not protected by normal blinking movements, without treatment, it can result in significant problems, including persistent dry eye, corneal scarring, persistent tearing, eye pain, and loss of vision. You can use artificial tears (eye drops) as often as every hour during the day to keep the eye moist. A moisturising eye ointment is typically used at night. You can use the ointment during the day, although it will blur your vision.
In extreme cases, the use of a patch may be recommended to protect the eye from permanent damage.