A number of complications can occur as a result of Bell's palsy, depending on the extent of nerve damage.

Most people fully recover from Bell's palsy within nine months. However, long-term complications of Bell’s palsy are more likely to occur if:

• you have been affected by a complete palsy, resulting in no movement at all (paralysis) on one side of your face
• you are over 60 years of age
• you had severe pain when you first experienced symptoms
• you have high blood pressure
• you have diabetes
• you are pregnant
• your facial nerve is badly damaged
• recovery doesn't begin until two months have passed
• there are no signs of recovery after four months

Up to 14% of people may find that Bell's palsy returns at a later date, on either side of the face. This is thought to be more likely if you have a family history of Bell's palsy.

Long-term complications

About two in 10 people experience long-term problems resulting from Bell’s palsy, which may include any of the following:

• Eye drying and corneal ulceration – Corneal ulceration can occur when the eyelid is too weak to close completely and the protective tear film becomes less effective. This can lead to infection and cause blindness.
• Facial weakness – permanent facial weakness is seen in 20-30% of people after Bell's palsy. Some children are born with facial palsy and others develop weakness after operations or injury to the facial nerve. Specialists in a facial palsy clinic can help treat facial weakness.
• Speech problems – This can occur as a result of damage to the facial muscles.
• Eye-mouth synkinesias – This happens as a result of the nerve in your face growing back in a different way. It can cause your eye to wink when eating, laughing or smiling. Sometimes it can become so severe that the eye can close completely during meals.
• Facial tightness (contracture) – This is where your facial muscles are permanently tense. It can lead to facial disfigurement such as the eye becoming smaller, the cheek becoming more bulky, or the line between the nose and the mouth becoming deeper.
• Loss or reduced sense of taste – This can happen if any damaged nerves do not repair properly.
• Tears when eating, known as 'crocodile tears'.

Ramsay Hunt syndrome

If you have Bell’s palsy caused by the varicella-zoster virus, there is a possibility you could develop a rare, but serious, condition called Ramsay Hunt syndrome.

Ramsay Hunt syndrome can cause blisters to appear on your tongue and the inside of your ears. It can usually be treated with steroids and antiviral medication.