Hemifacial spasm (HFS) is a neurological disorder manifested by twitching on one side of the face due to involuntary contractions of the eyelid and other facial muscles. It usually begins gradually ...

you've experienced a muscle spasm, also referred to as a charley horse. These spasms, often felt in areas like the neck, legs ...

Onabotulinumtoxin A is under clinical development by AbbVie and currently in Phase III for Unspecified Musculoskeletal Disorders.