‌Hemifacial spasm is a disorder of the nerves and muscles that causes nonpainful involuntary twitching on one side of the face. Many people refer to hemifacial spasms as lip muscle spasms. Hemifacial ...

Anxiety may sometimes cause any of your muscles to start twitching. It may be caused by neurotransmitters being released. Treating anxiety is the best way to prevent anxiety twitching. Twitching is ...