A muscle spasm, also known as a cramp, twitch or charley horse, is the sudden and involuntary forced contraction of a muscle. Experts weigh in on what's behind this sudden discomfort, when to be ...

A muscle spasm, also known as a cramp, twitch or charley horse, is the sudden, involuntary forced contraction of a muscle. Here are the main causes.

Discover the science behind hypnic jerks, involuntary muscle spasms during sleep, and how to manage them effectively.

A muscle spasm — also known as a charley horse, muscle cramp or twitch — is a sudden, involuntary movement in one or more muscles. Common causes include stress, exercise, or dehydration ...

Muscle spasms, also known as muscle cramps, are sudden, involuntary contractions of one or more muscles. They can be painful and brief but are usually harmless and resolve quickly.

Medically reviewed by Nicholas R. Metrus, MD Hemifacial spasm (HFS) is a rare movement disorder that causes involuntary muscle contractions on one side of the face. It typically starts with ...

Blepharospasm describes a condition where a person experiences an involuntary spasm of the muscles surrounding the eyelid. “Blepharo” refers to the eyelids, while “spasm” describes ...

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.