Facial Palsy

Symptoms of Bell's palsy, a neurological disorder that causes facial paralysis or weakness, include:

Facial weakness or paralysis: Usually occurs on one side of the face and can range from mild weakness to total paralysis
Drooping: A drooping eyelid or corner of the mouth is common
Drooling: Drooling from one side of the mouth is a common symptom
Dry mouth: A dry mouth can occur
Loss of taste: A loss of taste on the front two-thirds of the tongue is common
Dry or watering eye: Excessive tearing from one eye or a dry eye can occur
Headache: A headache can occur
Pain: Pain around the jaw or pain in or behind the ear on the affected side can occur
Sensitivity to sound: Hypersensitivity to sound in the affected ear can occur
Difficulty closing the eye: Difficulty closing the eye on the affected side of the face can occur
The term facial palsy generally refers to weakness of the facial muscles, mainly resulting from temporary or permanent damage to the facial nerve.

When a facial nerve is either non-functioning or missing, the muscles in the face do not receive the necessary signals in order to function properly. This results in paralysis of the affected part of the face, which can affect movement of the eye(s) and/or the mouth, as well as other areas.
There are different degrees of facial paralysis: sometimes only the lower half of the face is affected, sometimes one whole side of the face is affected and in some cases both sides of the face are affected.