what causes facial twitching

Facial twitching, also known as hemifacial spasm, is a nervous system condition in which the muscles on one side of the face twitch involuntarily. The most common cause of hemifacial spasm is a blood vessel touching or pulsing against a facial nerve, but it can also be caused by a facial nerve injury or a tumor. Sometimes, there is no known cause for the twitching. The twitching usually starts around the eye and spreads to other facial muscles on the same side of the face over time. Stress, anxiety, and fatigue are common triggers for hemifacial spasm. Treatment options include medication, botulinum toxin (Botox) injections, or surgery.