‌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 ...

Whenever I get severely anxious, there's a small muscle beneath my throat that twitches consistently for at least a few days, until it goes away on its own. Before I went to my doctor about it, though ...