Bell’s palsy is a disorder of the facial nerve, the seventh cranial nerve. This condition causes partial paralysis on one side of the face, affecting the muscles of facial expression. Bell’s palsy usually occurs in adults and develops suddenly.

Symptoms of Bell’s palsy include the inability to smile on one side or close one eyelid completely, decreased tear production and sense of taste, blurry vision, and distorted hearing.

The causes of Bell’s palsy are varied. In most cases, the cause is never identified, but it is believed that Bell’s palsy often develops secondary to a viral inflammation. Other causes include activation of the body’s immune system and changes in blood flow. Bell’s palsy is more common in patients with diabetes and in pregnant women.

Most of the time, Bell’s palsy disappears on its own after a few months. Eye lubricants may be used to prevent complications. In some cases, corticosteroid or antiviral drugs may be used to help in the treatment of this condition.

(c) 2007 The American Academy of Ophthalmology