You're relaxing on the sofa when suddenly your eyelid starts twitching. Or perhaps it's a muscle in your arm, your leg, or ...

Night leg cramps, or nocturnal leg cramps, are sudden, involuntary muscle contractions that usually occur in the calves, feet, or thighs during rest or sleep. These painful spasms can last from a few ...

Stiff person syndrome (SPS) causes you to have muscle stiffness and spasms, often triggered by sudden noises or touch. You can use medications like muscle relaxants and anticonvulsants to relieve ...

Spastic hemiplegia is the most common type of cerebral palsy. This causes symptoms in one-half of their body — you might experience pain, muscle stiffness, and lack of muscle control. Share on ...

Infectious agents can cause muscle twitching and spasms, too. The most commonly known is probably tetanus, which causes a phenomenon called lockjaw, where the neck and jaw muscles contract to the ...