Bells palsy is a nonpermanent condition that causes the facial muscles to weaken or become paralyzed. Up to 70% of the cases of Bell's palsy can be linked to the presence of the oral herpes simplex virus (HSV-1). The virus seems to cause an inflammation of the facial nerve that controls the muscles of the face, causing paralysis of the face and the inability to blink an eye.

Most people either wake up to find they have Bells palsy, or have symptoms such as a dry eye or tingling around their lips that progress during the day, although occasionally symptoms may take a few days to be recognized. The degree of paralysis should peak within several days of onset, never in longer than 2 weeks. A warning sign may be neck pain, or pain in or behind the ear prior to palsy, but it is not usually recognized in first-time cases.

In 90% of cases, treatment with an anti-viral and a steroid-based anti-inflammatory are recommended and improvement should be expected in 2 to 4 weeks, and full recovery within 3 to 6 months. In 10% of cases, if treatment doesn’t work, than reconstructice surgery is suggested.